Today's Message Index:
----------------------
1. 02:54 AM - Re: Question about Gross Weight (Jack Phillips)
2. 03:42 AM - Re: Sat. Both sad and happy (John Dilatush)
3. 04:18 AM - Landing Gear Placement (John Dilatush)
4. 05:02 AM - Re: Sat. Both sad and happy (John_Duprey@vmed.org)
5. 05:29 AM - Re: Landing Gear Placement (kirk)
6. 06:04 AM - prop testing (Oscar Zuniga)
7. 06:25 AM - Re: Landing Gear Placement (del magsam)
8. 07:36 AM - Re: Press. oiled A (Les Schubert)
9. 07:36 AM - Re: Press. oiled A (Les Schubert)
10. 08:33 AM - Re: Landing Gear Placement (Christian Bobka)
11. 08:36 AM - Re: Landing Gear Placement (John Dilatush)
12. 12:30 PM - Re: Landing Gear Placement (del magsam)
13. 02:02 PM - Re: Landing Gear Placement (DRHALL223@aol.com)
14. 03:00 PM - Re: Landing Gear Placement (walter evans)
15. 03:00 PM - Re: Landing Gear Placement (Christian Bobka)
16. 03:12 PM - Re: long fuse gear (D.Dale Johnson)
17. 05:15 PM - Re: long fuse gear (Richard Navratril)
18. 06:29 PM - Re: Landing Gear Placement (John Dilatush)
19. 06:53 PM - Re: long fuse gear (Kip & Beth Gardner)
20. 08:08 PM - Re: Landing Gear Placement (del magsam)
21. 08:12 PM - Re: Landing Gear Placement (Dmott9@aol.com)
22. 08:50 PM - Re: Landing Gear Placement (ZigoDan@aol.com)
23. 10:28 PM - blast it (Christian Bobka)
24. 10:35 PM - I added this too (Christian Bobka)
25. 10:50 PM - Ron skip and John (Christian Bobka)
26. 11:31 PM - Re: Question about Gross Weight (clif)
Message 1
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Question about Gross Weight |
--> Pietenpol-List message posted by: "Jack Phillips" <jackphillips@earthlink.net>
Jon,
Chris is right, up to a point. The gross weight is basically set by some
structural parameter in the aircraft, usually the wing spar or the landing
gear. You hear of a plane being stressed to +/- 10 G's, well that means
the structure can handle a certain limit load, and depending on how many G's
the designer wants the plane to be good for, he divides the limit load by
that number of G's and voila - the gross weight pops out!
When I was a young engineer just out of college and was working for General
Dynamics on the F-16 initial design (sad that a plane designed in 1975 is
still one of our front line fighters), the initial gross weight of the plane
was 23,000 lbs. (which meant it could go supersonic straight up with its
25,000 lb. thrust engine). Later, some mods to the landing gear enabled it
to takeoff with more fuel on board in external tanks and the takeoff gross
weight was increased to 37,000 lbs, but its maneuvering gross weight was
still 23,000.
In other words, the gross weight is somewhat arbitrary. However, be aware
that stall speed is a variable and goes up with gross weight. It is quite
possible with a robust structured airplane to have a gross weight that is
structurally safe but simply can't fly because the stall speed is too high.
For my Pietenpol, I've figured on a gross weight of around 1100 lbs.
Jack
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Christian
Bobka
Subject: RE: Pietenpol-List: Question about Gross Weight
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Jon,
For an experimental, it is whatever you want it to be. Believe it or not.
You set the rules. No kidding.
Chris Bobka
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jon
Botsford
Subject: Pietenpol-List: Question about Gross Weight
--> Pietenpol-List message posted by: "Jon Botsford" <botsford7@hot.rr.com>
Can someone on this list tell me how the Gross Weight is calculated for an
aircraft?
Jon Botsford
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Sat. Both sad and happy |
--> Pietenpol-List message posted by: "John Dilatush" <dilatush@amigo.net>
----- Original Message -----
From: <Isablcorky@aol.com>
<Lincol99@aol.com>; <christinedigsjazz@shaw.ca>; <wayfollower@cox.net>;
<claudiabartlett@austin.rr.com>; <T_FIN@Compuserve.com>;
<hmposer@charter.net>; <Howdyhilary@aol.com>; <fleece@cox-internet.com>;
<NewtonIvy@webtv.net>; <jamestownesimmons@yahoo.com>;
<jbrainis@sport.rr.com>; <LCJELKS@aol.com>; <JimNikls@aol.com>;
<Herzog807@msn.com>; <Jajouett@aol.com>; <Leeortho@aol.com>;
<LGililland@msn.com>; <Linda@huarch.com>; <tvlux@cox.net>;
<MAGSOUR@aol.com>; <Marionle35@aol.com>; <Mvphipps39@aol.com>;
<rchapman@andersonsmith.com>; <RobertBeachbum@aol.com>;
<nfn00979@naples.net>; <TomTravis@aol.com>; <wbeevans@worldnet.att.net>;
<craigwilcox@peoplepc.com>
Subject: Pietenpol-List: Sat. Both sad and happy
+++++++++++++++++++
Corky,
I share your feelings, both about the shuttle tragedy and the euphoria of
your first ride. Thanks for sharing with us.
Congratulations!
John
+++++++++++++++++++
> --> Pietenpol-List message posted by: Isablcorky@aol.com
>
> Pieters and Friends,
> Yesterday began very sad for our country and some space participants and
> their families. This we all regret deeply.
>
> Yesterday, my test pilot Mr. Edwin Johnson, finally agreed to let me fly
in
> my airplane. Sounds funny doesn't it. He had test flown the first 25 hrs
and
> 36 minutes as required by the FAA before carrying a passenger ( that's
me).
> Earlier in the afternoon I had cranked up N41CC and taxied up and down the
> runway waiting for him. The tailwheel didn't answer to helm as I wanted it
so
> I came in and made some changes. Finally he arrived and said he would
ride
> front hole and I would fly from the rear, where else? It took him 2 prop
> swings before it started. ( I started it on the first swing earlier). We
> talked about our signals etc before we taxied out for run up. Finally I
went
> to the north end of Lucien and did a few vrooms eased the throttle forward
> and felt that 65 Continental try to force me through the seat back. Didn't
> even forget to pressure the rudder to the right when the tail lifted.
Didn't
> know when we left the ground as it was so quick. Kicked in a little right
> crab, ( SW wind), and she climbed like an angel on her way home. Made my
left
> climbing turn and the ball stayed centered. Man, I was livin. Went up to
1K,
> 130 deg, to go chase hundreds of white pelicans down on the roaring Red. A
> beautiful bird, most people have never seen them from above to see the
> beautiful black-top wing tips. Anyway my front holer directed me to Desoto
> Parish Airport for some attempts to land this airplane. I had failed to
tell
> him that I had not landed a tail wheel airplane since 1972. Oh well, he
would
> soon find out. I made my usual Kamakazi approach as he just sat up there
> stunned. Came on down to 18 and leveled off to land as if I had been
landing
> a big bird. Was pretty high and did I ever spread the gears, ( dropped
in). I
> was embarrased. We went around again and on base he took it to show me how
> well a Piet would slip. On final I slipped it and it was like the old L-16
in
> '51. He applauded this landing. Hell, any landing would have beat that
first
> one. We left Desoto. Forgot to mention that between the Pelicans and
Desoto
> we went up to 2500 for some steeeeeeeep turns, sslooooooooooow flying and
> some stalls, power on and half on.
> All went well. I felt right at home.
> Next we went to a sod duster operation strip. First landing, kinda bad,
again
> flairing out too high. Next one he applauded me once again. By then the
sun
> had set and it was beginning to cool down in 41CC so we came home. Landed
at
> Lucien, again kinda high but ground control was OK. That Lucien runway
can't
> be any wider 12 or 15 feet.
> I guess you might say this was part of what they call a bi-annual. His
only
> comment was that we need to do it again as soon as we can get another
> beautiful day. As all of you noted, the skies in East Texas and Western La
> yesterday were as clear as I ever remember.
> I ended the day feeling like a popsickle but very pleased to have piloted
our
> own creation. Joe Czalicka and I. Those building Piets, don't stop, it's
> worth all the work.
>
> Corky in La
>
>
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Landing Gear Placement |
--> Pietenpol-List message posted by: "John Dilatush" <dilatush@amigo.net>
Pieters,
I too, struggled with the placement of the gear on my long fuselage, and finally
decided to use the simple weight and balance spreadsheet that I had been using
on my computer.
When I began building the plane, I made up a simple spreadsheet on the computer
which listed the estimated weight and the moments of each major component of
the plane such as engine, wing, fuel tank, pilot, passenger etc.
Then as each part was built the actual weight was put into the spreadsheet and
the revised W&B was automatically computed.
When it came to the placement of the gear, I figured that I wanted to have the
ground contact of the wheels to be about 12 degrees forward of the CG. Turned
out to be perfect. I can use the brakes pretty hard without any tendency to
nose over, (the brakes are not that effective)yet it is light enough on the tailwheel,
(12 lbs) to handle easily on the ground.
Generally speaking, the further forward the gear is, the more squirrely the plane
is on take off and landings, but too far aft and it becomes too sensitive to
nosing over under braking effort.
Hope this helps,
John, NX114D
Message 4
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Sat. Both sad and happy |
02/03/2003 08:02:12 AM
--> Pietenpol-List message posted by: John_Duprey@vmed.org
Congratulations Corky!!!!!!
Isablcorky@aol.com@matronics.com on 02/02/2003 06:31:28 PM
Please respond to pietenpol-list@matronics.com
Sent by: owner-pietenpol-list-server@matronics.com
Lincol99@aol.com, christinedigsjazz@shaw.ca, wayfollower@cox.net,
claudiabartlett@austin.rr.com, T_FIN@Compuserve.com,
hmposer@charter.net, Howdyhilary@aol.com, fleece@cox-internet.com,
NewtonIvy@webtv.net, jamestownesimmons@yahoo.com,
jbrainis@sport.rr.com, LCJELKS@aol.com, JimNikls@aol.com,
Herzog807@msn.com, Jajouett@aol.com, Leeortho@aol.com,
LGililland@msn.com, Linda@huarch.com, tvlux@cox.net,
MAGSOUR@aol.com, Marionle35@aol.com, Mvphipps39@aol.com,
rchapman@andersonsmith.com, RobertBeachbum@aol.com,
nfn00979@naples.net, TomTravis@aol.com, wbeevans@worldnet.att.net,
craigwilcox@peoplepc.com
cc:
Subject: Pietenpol-List: Sat. Both sad and happy
--> Pietenpol-List message posted by: Isablcorky@aol.com
Pieters and Friends,
Yesterday began very sad for our country and some space participants and
their families. This we all regret deeply.
Yesterday, my test pilot Mr. Edwin Johnson, finally agreed to let me fly in
my airplane. Sounds funny doesn't it. He had test flown the first 25 hrs
and
36 minutes as required by the FAA before carrying a passenger ( that's me).
Earlier in the afternoon I had cranked up N41CC and taxied up and down the
runway waiting for him. The tailwheel didn't answer to helm as I wanted it
so
I came in and made some changes. Finally he arrived and said he would ride
front hole and I would fly from the rear, where else? It took him 2 prop
swings before it started. ( I started it on the first swing earlier). We
talked about our signals etc before we taxied out for run up. Finally I
went
to the north end of Lucien and did a few vrooms eased the throttle forward
and felt that 65 Continental try to force me through the seat back. Didn't
even forget to pressure the rudder to the right when the tail lifted.
Didn't
know when we left the ground as it was so quick. Kicked in a little right
crab, ( SW wind), and she climbed like an angel on her way home. Made my
left
climbing turn and the ball stayed centered. Man, I was livin. Went up to
1K,
130 deg, to go chase hundreds of white pelicans down on the roaring Red. A
beautiful bird, most people have never seen them from above to see the
beautiful black-top wing tips. Anyway my front holer directed me to Desoto
Parish Airport for some attempts to land this airplane. I had failed to
tell
him that I had not landed a tail wheel airplane since 1972. Oh well, he
would
soon find out. I made my usual Kamakazi approach as he just sat up there
stunned. Came on down to 18 and leveled off to land as if I had been
landing
a big bird. Was pretty high and did I ever spread the gears, ( dropped in).
I
was embarrased. We went around again and on base he took it to show me how
well a Piet would slip. On final I slipped it and it was like the old L-16
in
'51. He applauded this landing. Hell, any landing would have beat that
first
one. We left Desoto. Forgot to mention that between the Pelicans and Desoto
we went up to 2500 for some steeeeeeeep turns, sslooooooooooow flying and
some stalls, power on and half on.
All went well. I felt right at home.
Next we went to a sod duster operation strip. First landing, kinda bad,
again
flairing out too high. Next one he applauded me once again. By then the sun
had set and it was beginning to cool down in 41CC so we came home. Landed
at
Lucien, again kinda high but ground control was OK. That Lucien runway
can't
be any wider 12 or 15 feet.
I guess you might say this was part of what they call a bi-annual. His only
comment was that we need to do it again as soon as we can get another
beautiful day. As all of you noted, the skies in East Texas and Western La
yesterday were as clear as I ever remember.
I ended the day feeling like a popsickle but very pleased to have piloted
our
own creation. Joe Czalicka and I. Those building Piets, don't stop, it's
worth all the work.
Corky in La
Message 5
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: kirk <kirkh@unique-software.com>
You can also check out the landing gear design info from one of
Pazmany's books at.
http://mykitplane.com/Planes/filesList2.cfm?AlbumID=5
It suggests that the angle from the forward most CG to the contact
point of the wheels be 12 to 15 degrees ahead. There is some other
info in the article also.
I am in the middle of gear building now and it is one of the most
difficult, but fun learning experiences so far.
Kirk
Message 6
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
--> Pietenpol-List message posted by: "Oscar Zuniga" <taildrags@hotmail.com>
Howdy, Pieters-
To those of you who have a Corvair on your Piet and who are flying or
getting ready to, I have an offer. I just got a brand-new 62x34 Tennessee
Props wood prop for the Corvair/Pietenpol. My engine won't be running for a
while and definitely won't be installed on a Piet for a good long while, so
I stand ready to loan my prop out for testing. The intent is not to have it
sitting around, but rather for someone who is flying or on the verge of
flying and who could get some useful data from it and maybe get in the air a
bit sooner than if you had to order one and wait for it.
The prop is through-bored for the safety shaft, 3" thick, left-hand turning,
SAE #1 bolt pattern for AN6 bolts. I do not have a crush plate for it yet,
but will soon (and all wood props must have one).
Anyone interested, let me know off-line and we'll talk. The prop is crated
for shipping (I just got it Friday) and it's a beauty. Maybe I'll take a
picture and put it on my website.
Oscar Zuniga
San Antonio, TX
mailto: taildrags@hotmail.com
website at http://www.flysquirrel.net
Message 7
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: del magsam <farmerdel@rocketmail.com>
Hi John
what was different about your craft that you had to
change gear location from the plans, and from the
location that 500 other pieters placed theirs?
thanks
Del
--- John Dilatush <dilatush@amigo.net> wrote:
> --> Pietenpol-List message posted by: "John
> Dilatush" <dilatush@amigo.net>
>
> Pieters,
>
> I too, struggled with the placement of the gear on
> my long fuselage, and finally decided to use the
> simple weight and balance spreadsheet that I had
> been using on my computer.
>
> When I began building the plane, I made up a simple
> spreadsheet on the computer which listed the
> estimated weight and the moments of each major
> component of the plane such as engine, wing, fuel
> tank, pilot, passenger etc.
>
> Then as each part was built the actual weight was
> put into the spreadsheet and the revised W&B was
> automatically computed.
>
> When it came to the placement of the gear, I figured
> that I wanted to have the ground contact of the
> wheels to be about 12 degrees forward of the CG.
> Turned out to be perfect. I can use the brakes
> pretty hard without any tendency to nose over, (the
> brakes are not that effective)yet it is light enough
> on the tailwheel, (12 lbs) to handle easily on the
> ground.
>
> Generally speaking, the further forward the gear is,
> the more squirrely the plane is on take off and
> landings, but too far aft and it becomes too
> sensitive to nosing over under braking effort.
>
> Hope this helps,
>
> John, NX114D
>
>
>
> Contributions
> any other
> Forums.
>
> latest messages.
> List members.
>
> http://www.matronics.com/subscription
> http://www.matronics.com/FAQ/Pietenpol-List.htm
>
Digests:http://www.matronics.com/digest/pietenpol-list
> http://www.matronics.com/archives
> http://www.matronics.com/photoshare
> http://www.matronics.com/emaillists
>
>
>
>
>
=====
Del-New Richmond, Wi
"farmerdel@rocketmail.com"
Message 8
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Press. oiled A |
--> Pietenpol-List message posted by: Les Schubert <leskarin@telus.net>
Leon
I have always stayed with the babbitt. I have found that with pressure it
will hang together at 4500 rpm for many miles of road use, way faster than
we will run in a airplane. I am not sure I am a big fan of thin shell
bearings in a A especially at high power settings as the A crank is still
quite flexible and the babbitt will "adjust" to the required clearance
which the thinly coated shell bearings can't. Maybe this doesn't really
happen but it suits my experience.
Les
At 11:25 PM 02/02/2003 -0600, you wrote:
>--> Pietenpol-List message posted by: lshutks@webtv.net (Leon Stefan)
>
>Les: When you drill and pressure oiled the crank, did you stay with the
>babbit, or go with insert bearings? Leon S Hutchinson Ks.
>
>
Message 9
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Press. oiled A |
--> Pietenpol-List message posted by: Les Schubert <leskarin@telus.net>
Dan
It seems like every guy I have talked to always wishes he had a little more
power.
Getting more power out of a A or most any engine is pretty easy, it is
getting them to
"live" that is the challenge. Henry didn't drill cranks till the V 8 which
came out right
after the A, and went from 40 hp to 85 hp with almost the same displacement.
I am not a big fan of insert bearings for the A crank, but maybe they work.
A properly done babbitt job with pressure works just fine for extra power
engines.
Les
At 12:42 AM 03/02/2003 -0500, you wrote:
>--> Pietenpol-List message posted by: ZigoDan@aol.com
>
>I assume you guys are going to turn up the heat in your A powered ships. The
>pressured oil supply is not needed if turning Pietenpols recommended RPM.
>But I understand that it is nice to have. The engine is able to produce more
>power than designed for. Better breathing is what I have understood to help
>the most, increase the intake CFMS. The insert bearings I have seen
>available use a center thrust, is this the norm? If so it would not seem to
>be a good idea, since the thrust loads need to stay were they are for
>aircraft use.
>P.S. I have an A engine with most machine work done, and new bearings for
>$550.00 anyone interested email me at zigodan@aol.com.
>
>Dan
>
>
Message 10
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Landing Gear Placement |
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Del,
as my recent post on this subject says, if you build the long "corvair"
fuselage, NO GEAR was ever shown on the drawings. So how do yo know where
it should be? The point of my presentation is that if you don't know where
it is to be per the drawings then this is one man's (my) best guess. Also,
I use Sky Gypsy as a prime example of a much beloved Piet that was built one
way and then promptly modified to be manageable by a very able pilot. May I
suggest that the 500 less the Sky Gypsy are the 499 piets that never fly?
Chris
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of del
magsam
Subject: Re: Pietenpol-List: Landing Gear Placement
--> Pietenpol-List message posted by: del magsam <farmerdel@rocketmail.com>
Hi John
what was different about your craft that you had to
change gear location from the plans, and from the
location that 500 other pieters placed theirs?
thanks
Del
--- John Dilatush <dilatush@amigo.net> wrote:
> --> Pietenpol-List message posted by: "John
> Dilatush" <dilatush@amigo.net>
>
> Pieters,
>
> I too, struggled with the placement of the gear on
> my long fuselage, and finally decided to use the
> simple weight and balance spreadsheet that I had
> been using on my computer.
>
> When I began building the plane, I made up a simple
> spreadsheet on the computer which listed the
> estimated weight and the moments of each major
> component of the plane such as engine, wing, fuel
> tank, pilot, passenger etc.
>
> Then as each part was built the actual weight was
> put into the spreadsheet and the revised W&B was
> automatically computed.
>
> When it came to the placement of the gear, I figured
> that I wanted to have the ground contact of the
> wheels to be about 12 degrees forward of the CG.
> Turned out to be perfect. I can use the brakes
> pretty hard without any tendency to nose over, (the
> brakes are not that effective)yet it is light enough
> on the tailwheel, (12 lbs) to handle easily on the
> ground.
>
> Generally speaking, the further forward the gear is,
> the more squirrely the plane is on take off and
> landings, but too far aft and it becomes too
> sensitive to nosing over under braking effort.
>
> Hope this helps,
>
> John, NX114D
>
>
> Contributions
> any other
> Forums.
>
> latest messages.
> List members.
>
> http://www.matronics.com/subscription
> http://www.matronics.com/FAQ/Pietenpol-List.htm
>
Digests:http://www.matronics.com/digest/pietenpol-list
> http://www.matronics.com/archives
> http://www.matronics.com/photoshare
> http://www.matronics.com/emaillists
>
>
=====
Del-New Richmond, Wi
"farmerdel@rocketmail.com"
Message 11
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: "John Dilatush" <dilatush@amigo.net>
----- Original Message -----
From: "del magsam" <farmerdel@rocketmail.com>
Subject: Re: Pietenpol-List: Landing Gear Placement
+++++++++++++++++++++
Del,
To answer your question: Each Pietenpol that has been built seems to vary
from the plans some according to the engine used, builder's preference on
details, woods used, finishes applied and on and on. All of these changes
result in a different CG location. Since the ground handling is dependent
on the landing gear location and the landing gear location is dependent upon
the CG (both horizontal and vertical) then each gear location should be
figured for the particular plane if one is to get the kind of handling he is
looking for. This is one of the challenges of building your own plane from
plans rather than from a kit.
In my case, I am running a heavier powerplant than usual, have added brakes,
tailwheel, seat padding, electrical system, ELT, cowl tank and other
modifications, all of which change the CG from the plans. Although the gear
location is changed by only a couple of inches from the plans and is not
super critical, I chose to be precise.
John
+++++++++++++
> --> Pietenpol-List message posted by: del magsam
<farmerdel@rocketmail.com>
>
> Hi John
> what was different about your craft that you had to
> change gear location from the plans, and from the
> location that 500 other pieters placed theirs?
> thanks
> Del
> --- John Dilatush <dilatush@amigo.net> wrote:
> > --> Pietenpol-List message posted by: "John
> > Dilatush" <dilatush@amigo.net>
> >
> > Pieters,
> >
> > I too, struggled with the placement of the gear on
> > my long fuselage, and finally decided to use the
> > simple weight and balance spreadsheet that I had
> > been using on my computer.
> >
> > When I began building the plane, I made up a simple
> > spreadsheet on the computer which listed the
> > estimated weight and the moments of each major
> > component of the plane such as engine, wing, fuel
> > tank, pilot, passenger etc.
> >
> > Then as each part was built the actual weight was
> > put into the spreadsheet and the revised W&B was
> > automatically computed.
> >
> > When it came to the placement of the gear, I figured
> > that I wanted to have the ground contact of the
> > wheels to be about 12 degrees forward of the CG.
> > Turned out to be perfect. I can use the brakes
> > pretty hard without any tendency to nose over, (the
> > brakes are not that effective)yet it is light enough
> > on the tailwheel, (12 lbs) to handle easily on the
> > ground.
> >
> > Generally speaking, the further forward the gear is,
> > the more squirrely the plane is on take off and
> > landings, but too far aft and it becomes too
> > sensitive to nosing over under braking effort.
> >
> > Hope this helps,
> >
> > John, NX114D
> >
> >
> >
> > Contributions
> > any other
> > Forums.
> >
> > latest messages.
> > List members.
> >
> > http://www.matronics.com/subscription
> > http://www.matronics.com/FAQ/Pietenpol-List.htm
> >
> Digests:http://www.matronics.com/digest/pietenpol-list
> > http://www.matronics.com/archives
> > http://www.matronics.com/photoshare
> > http://www.matronics.com/emaillists
> >
> >
> >
> >
> >
>
>
> =====
> Del-New Richmond, Wi
> "farmerdel@rocketmail.com"
>
>
Message 12
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Landing Gear Placement |
--> Pietenpol-List message posted by: del magsam <farmerdel@rocketmail.com>
--- Christian Bobka <bobka@charter.net> wrote:
> --> Pietenpol-List message posted by: "Christian
> Bobka" <bobka@charter.net>
>
> Del,
>
> as my recent post on this subject says, if you build
> the long "corvair"
> fuselage, NO GEAR was ever shown on the drawings.
> So how do yo know where
> it should be? The point of my presentation is that
> if you don't know where
> it is to be per the drawings then this is one man's
> (my) best guess. Also,
> I use Sky Gypsy as a prime example of a much beloved
> Piet that was built one
> way and then promptly modified to be manageable by a
> very able pilot. May I
> suggest that the 500 less the Sky Gypsy are the 499
> piets that never fly?
>
> Chris
If the gear location isn't indicated on the long fuse
option plans, I would assume it is not changed from
the original plans, which is where I mounted mine. And
it made sense to put the gear mounts per plans because
that is where the upright longeron braces connect the
wing connection hardware to the gear connection
hardware. to directly absorb the weight of the wing on
landing. So...should I reconsider? or will that work.
thanks for your input
Del
=====
Del-New Richmond, Wi
"farmerdel@rocketmail.com"
Message 13
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: DRHALL223@aol.com
Hey Folks,
In the papers I received with my plans there is a memo of sorts that talks to
the movement forward of the landing gear on the stretched fuselage version.
If there is any interest I could probably get it scanned and post it.
Dave Hall
Fayetteville, NC
Message 14
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: "walter evans" <wbeevans@worldnet.att.net>
Just jumping in with my two cents.
In spite of what engine you use or equiptment you put on, the CG is still in
the same window. Assuming that the gear is hooked to the same attach
points,
if you use the split gear, the only way to relocate the wheels is by
changing the style of the "V". If you do this, as the gear moves thru it's
range of motion while the bungees are flexing, the toe-in/toe-out
caster/camber is all going to be different from original.
Except for moving engine forward about 2" (A-65 long fuselage) to
compensate for my fat arse, the CG is still in the window(way to the rear).
I built the split gear to the plans, and it seems to handle fine riding on
the mains waiting to leave the earth.
walt
----- Original Message -----
From: "del magsam" <farmerdel@rocketmail.com>
Subject: RE: Pietenpol-List: Landing Gear Placement
> --> Pietenpol-List message posted by: del magsam
<farmerdel@rocketmail.com>
>
>
> --- Christian Bobka <bobka@charter.net> wrote:
> > --> Pietenpol-List message posted by: "Christian
> > Bobka" <bobka@charter.net>
> >
> > Del,
> >
> > as my recent post on this subject says, if you build
> > the long "corvair"
> > fuselage, NO GEAR was ever shown on the drawings.
> > So how do yo know where
> > it should be? The point of my presentation is that
> > if you don't know where
> > it is to be per the drawings then this is one man's
> > (my) best guess. Also,
> > I use Sky Gypsy as a prime example of a much beloved
> > Piet that was built one
> > way and then promptly modified to be manageable by a
> > very able pilot. May I
> > suggest that the 500 less the Sky Gypsy are the 499
> > piets that never fly?
> >
> > Chris
> If the gear location isn't indicated on the long fuse
> option plans, I would assume it is not changed from
> the original plans, which is where I mounted mine. And
> it made sense to put the gear mounts per plans because
> that is where the upright longeron braces connect the
> wing connection hardware to the gear connection
> hardware. to directly absorb the weight of the wing on
> landing. So...should I reconsider? or will that work.
> thanks for your input
> Del
>
> =====
> Del-New Richmond, Wi
> "farmerdel@rocketmail.com"
>
>
Message 15
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Landing Gear Placement |
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Del,
The mounting points are the same. The mounting hardware is the same. The V
just changes shape as the axle is moved back. Looking at the wood gear
shown 1932 F & G Manual, the forward leg of the V is more vertical and
shorter than the aft leg of the V which is longer. As the axle moves back
the legs begin to equal out in length. This is needed on the long "corvair"
fuselage as used on sky gypsy because you moved the CG aft and you increased
vertical surface area aft.
There are three conditions:
1) low speed aircraft handling on ground with negligible total aerodynamic
effects.
2) high speed aircraft handling on the ground with considerable total
aerodynamic effects.
3) aircraft in flight. Landing gear has limited aerodynamic effects.
In case one, you are dealing with taxiing, speeding up for take off and
slowing down after landing. This is with little or no help from the rudder
due to slow speeds. The farther forward the gear is located on the
fuselage, the greater the distance between the CG and the gear axle. Also,
lowering the tail slides the gear even further forward. We are used to the
CG being defined as the point of rotation of all reactions but this only
applies in flight. If a wheel is touching the ground, then the wheel
contact point, which is just below the axle becomes the point of rotation
because that is where the airplane is "attached" to the ground. The greater
the distance between the CG and this ground "attachment" point, the harder
it is for the pilot to transition from ground mode to flight mode. Small
changes forward in axle placement greatly increase the tendency to ground
loop.
In addition, as the axle is moved forward, there is an increased side
surface area aft of the "attach" point of the aircraft with the ground.
With a forward axle, any crosswinds would cause the tail to swing right
around into the wind. Don't forget that any surface moved from in front to
behind the axle hurts you twice becuase forward of the axle it was helping
to counter what was behind the axle. Now it is adding to what is behind the
axle. Also, the distance from the axle to the end of the ship increases the
leverage that side surface area exerts in a crosswind. Granted, this may
increase rudder effectivity but we are dealing with a flying surface that is
trying to use air on the downwind side of the fuselage to move the fuselage
back toward the windward side. The downswind side of the fuselage is
essentially blanked out so the rudder has limited effectiveness.
In case two, a too far forward placement of the axle will cause increased
ground looping tendencies due to CG placement relative the axle and side
surface area relative the axle as noted in the previous paragraph. With
the axle too far forward, it will be virtually impossible to lift the tail
for takeoff until an abnormally high speed in ground roll is attained. A
tail wheel airplane is not designed for this. It will present a high drag
profile to the relative wind and the takeoff rolls will be too long. It
will also increase the structural loading on the tail with some pretty large
impact loads. You will be ripping the tail skid/wheel off on a regular
basis.
In case three, the too far forward placement of the gear would put vertical
surface area (the wheel sides) far forward of the CG. This will tend to
cancel the stabilizing effect of the vertical stabilizer. As cool as
covered spoked wheels look, this is a big reason why many that have used
spoked wheels with fabric covering have removed the fabric covering. The
two big vertical discs negated the stabilizing effects of the vertical
stabilizer.
In summary, the axle needs to placed as far aft as possible but with
consideration of limiting the tendency to noseover. Others posted messages
to this list indicating the degree angle that the axle needs to be forward
of the CG. This is do true but it truly neds to be understood. A picture
would really help to see what is meant. We tend to think of the CG as a
point on the wing where the ship balances. This is a valid CG location but
this is the longitudinal CG or the CG along the longitudinal axis. We need
to also consider the other axes. There is a CG about the vertical axis and
a CG about the lateral axis. Combine these three and you get a single point
about which all the mass of the aircraft is located. A guess on the
Pietenpol, with its high wing, is that it is located at or about the center
of the instrument panel. If you level the ship and then hang a plumb bob
from this point and then make the angle forward of this (someone else
mentioned it in an email a minute ago, was it 7 degrees?), your axle should
optimally lie on that line. This would be the axle location that is as far
back as possible yet far enought forward to keep you from nosing over.
I hope this helps.
Chris Bobka
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of del
magsam
Subject: RE: Pietenpol-List: Landing Gear Placement
--> Pietenpol-List message posted by: del magsam <farmerdel@rocketmail.com>
--- Christian Bobka <bobka@charter.net> wrote:
> --> Pietenpol-List message posted by: "Christian
> Bobka" <bobka@charter.net>
>
> Del,
>
> as my recent post on this subject says, if you build
> the long "corvair"
> fuselage, NO GEAR was ever shown on the drawings.
> So how do yo know where
> it should be? The point of my presentation is that
> if you don't know where
> it is to be per the drawings then this is one man's
> (my) best guess. Also,
> I use Sky Gypsy as a prime example of a much beloved
> Piet that was built one
> way and then promptly modified to be manageable by a
> very able pilot. May I
> suggest that the 500 less the Sky Gypsy are the 499
> piets that never fly?
>
> Chris
If the gear location isn't indicated on the long fuse
option plans, I would assume it is not changed from
the original plans, which is where I mounted mine. And
it made sense to put the gear mounts per plans because
that is where the upright longeron braces connect the
wing connection hardware to the gear connection
hardware. to directly absorb the weight of the wing on
landing. So...should I reconsider? or will that work.
thanks for your input
Del
=====
Del-New Richmond, Wi
"farmerdel@rocketmail.com"
Message 16
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: long fuse gear |
--> Pietenpol-List message posted by: "D.Dale Johnson" <dd5john@juno.com>
Kip
Center of axal to fire wall 21 "
It seems right.
Dale
Message 17
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: long fuse gear |
--> Pietenpol-List message posted by: "Richard Navratril" <horzpool@goldengate.net>
Dale
Are you to the point of final or close w/b yet? If so, how far back did
you have to rake your wing to get acceptable balance?
On my short Fuse Piet the wing is back almost 4". I am hoping to avoid
that, this time It makes getting into the rear cockpit somewhat
challanging. I installed the center section cutout but the trailing edge
ends dont allow much room.
Dick N.
----- Original Message -----
From: "D.Dale Johnson" <dd5john@juno.com>
Subject: Re: Pietenpol-List: long fuse gear
> --> Pietenpol-List message posted by: "D.Dale Johnson" <dd5john@juno.com>
>
> Kip
>
> Center of axal to fire wall 21 "
> It seems right.
> Dale
>
>
Message 18
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: "John Dilatush" <dilatush@amigo.net>
----- Original Message -----
From: "Christian Bobka" <bobka@charter.net>
Subject: RE: Pietenpol-List: Landing Gear Placement
++++++++++++++++++++
Chris,
Good explanation, you are absolutely right! Piet builders should understand
that wheel placement is relative to the center of gravity of the entire mass
and to use an arbitrary measurement such as "distance from the firewall" or
"in front of the leading edge" are only asking for trouble.
John
+++++++++++++++++++++++
> --> Pietenpol-List message posted by: "Christian Bobka"
<bobka@charter.net>
>
> Del,
>
> The mounting points are the same. The mounting hardware is the same. The
V
> just changes shape as the axle is moved back. Looking at the wood gear
> shown 1932 F & G Manual, the forward leg of the V is more vertical and
> shorter than the aft leg of the V which is longer. As the axle moves back
> the legs begin to equal out in length. This is needed on the long
"corvair"
> fuselage as used on sky gypsy because you moved the CG aft and you
increased
> vertical surface area aft.
>
> There are three conditions:
>
> 1) low speed aircraft handling on ground with negligible total aerodynamic
> effects.
>
> 2) high speed aircraft handling on the ground with considerable total
> aerodynamic effects.
>
> 3) aircraft in flight. Landing gear has limited aerodynamic effects.
>
>
> In case one, you are dealing with taxiing, speeding up for take off and
> slowing down after landing. This is with little or no help from the
rudder
> due to slow speeds. The farther forward the gear is located on the
> fuselage, the greater the distance between the CG and the gear axle. Also,
> lowering the tail slides the gear even further forward. We are used to
the
> CG being defined as the point of rotation of all reactions but this only
> applies in flight. If a wheel is touching the ground, then the wheel
> contact point, which is just below the axle becomes the point of rotation
> because that is where the airplane is "attached" to the ground. The
greater
> the distance between the CG and this ground "attachment" point, the harder
> it is for the pilot to transition from ground mode to flight mode. Small
> changes forward in axle placement greatly increase the tendency to ground
> loop.
>
> In addition, as the axle is moved forward, there is an increased side
> surface area aft of the "attach" point of the aircraft with the ground.
> With a forward axle, any crosswinds would cause the tail to swing right
> around into the wind. Don't forget that any surface moved from in front
to
> behind the axle hurts you twice becuase forward of the axle it was helping
> to counter what was behind the axle. Now it is adding to what is behind
the
> axle. Also, the distance from the axle to the end of the ship increases
the
> leverage that side surface area exerts in a crosswind. Granted, this may
> increase rudder effectivity but we are dealing with a flying surface that
is
> trying to use air on the downwind side of the fuselage to move the
fuselage
> back toward the windward side. The downswind side of the fuselage is
> essentially blanked out so the rudder has limited effectiveness.
>
> In case two, a too far forward placement of the axle will cause increased
> ground looping tendencies due to CG placement relative the axle and side
> surface area relative the axle as noted in the previous paragraph. With
> the axle too far forward, it will be virtually impossible to lift the tail
> for takeoff until an abnormally high speed in ground roll is attained. A
> tail wheel airplane is not designed for this. It will present a high drag
> profile to the relative wind and the takeoff rolls will be too long. It
> will also increase the structural loading on the tail with some pretty
large
> impact loads. You will be ripping the tail skid/wheel off on a regular
> basis.
>
> In case three, the too far forward placement of the gear would put
vertical
> surface area (the wheel sides) far forward of the CG. This will tend to
> cancel the stabilizing effect of the vertical stabilizer. As cool as
> covered spoked wheels look, this is a big reason why many that have used
> spoked wheels with fabric covering have removed the fabric covering. The
> two big vertical discs negated the stabilizing effects of the vertical
> stabilizer.
>
> In summary, the axle needs to placed as far aft as possible but with
> consideration of limiting the tendency to noseover. Others posted
messages
> to this list indicating the degree angle that the axle needs to be forward
> of the CG. This is do true but it truly neds to be understood. A picture
> would really help to see what is meant. We tend to think of the CG as a
> point on the wing where the ship balances. This is a valid CG location
but
> this is the longitudinal CG or the CG along the longitudinal axis. We
need
> to also consider the other axes. There is a CG about the vertical axis
and
> a CG about the lateral axis. Combine these three and you get a single
point
> about which all the mass of the aircraft is located. A guess on the
> Pietenpol, with its high wing, is that it is located at or about the
center
> of the instrument panel. If you level the ship and then hang a plumb bob
> from this point and then make the angle forward of this (someone else
> mentioned it in an email a minute ago, was it 7 degrees?), your axle
should
> optimally lie on that line. This would be the axle location that is as
far
> back as possible yet far enought forward to keep you from nosing over.
>
> I hope this helps.
>
> Chris Bobka
> -----Original Message-----
> From: owner-pietenpol-list-server@matronics.com
> [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of del
> magsam
> To: pietenpol-list@matronics.com
> Subject: RE: Pietenpol-List: Landing Gear Placement
>
>
> --> Pietenpol-List message posted by: del magsam
<farmerdel@rocketmail.com>
>
>
> --- Christian Bobka <bobka@charter.net> wrote:
> > --> Pietenpol-List message posted by: "Christian
> > Bobka" <bobka@charter.net>
> >
> > Del,
> >
> > as my recent post on this subject says, if you build
> > the long "corvair"
> > fuselage, NO GEAR was ever shown on the drawings.
> > So how do yo know where
> > it should be? The point of my presentation is that
> > if you don't know where
> > it is to be per the drawings then this is one man's
> > (my) best guess. Also,
> > I use Sky Gypsy as a prime example of a much beloved
> > Piet that was built one
> > way and then promptly modified to be manageable by a
> > very able pilot. May I
> > suggest that the 500 less the Sky Gypsy are the 499
> > piets that never fly?
> >
> > Chris
> If the gear location isn't indicated on the long fuse
> option plans, I would assume it is not changed from
> the original plans, which is where I mounted mine. And
> it made sense to put the gear mounts per plans because
> that is where the upright longeron braces connect the
> wing connection hardware to the gear connection
> hardware. to directly absorb the weight of the wing on
> landing. So...should I reconsider? or will that work.
> thanks for your input
> Del
>
> =====
> Del-New Richmond, Wi
> "farmerdel@rocketmail.com"
>
>
Message 19
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: long fuse gear |
--> Pietenpol-List message posted by: Kip & Beth Gardner <kipandbeth@earthlink.net>
At 10:27 PM -0500 02/02/03, Waytogopiet@aol.com wrote:
>--> Pietenpol-List message posted by: Waytogopiet@aol.com
>
>In a message dated 2/2/2003 8:04:58 PM Central Standard Time,
>kipandbeth@earthlink.net writes:
>
>> I can ask him for details or make measurements for anyone that wants them
>
>Kip,
>I would very much appreciate any info in this regard that Frank can pass
>along. I have the long fuselage with the Model A and the solid wood gear, the
>same as his. I had built and installed the gear before the thread began on
>this subject. Of course that gear was intended for the original FGM version.
>I positioned mine in the location of the second version ("new, improved")
>which is probably equally wrong but I wanted to resist making any changes
>before doing my w&b and seeing what my tailwheel weight was. There may be
>meaningful differences dpending on whether Frank used fir or spruce on his
>fuselage. I did make a concerted effort to keep mine light in the
>tailfeathers and used spruce throughout. I'm fully covered, painted and
>complete and hopefully will be doing my final w&b this weekend. Thanks agin
>for the offer. Don Hicks
Don,
I will ask Frank about his W&B the next time I see him - might be a few
weeks - I'm not getting out to the airport as much during the winter. Then
it's a question of whether or not he's there too, although he's pushing
hard to finish up the Waco, so he's there pretty regularly.
I'll at least try to get out there for a bit this weekend & measure the
firewall to axle distance on Sky Gypsy & will post it on the list when I do.
Frank & his Dad built the plane out of 'conventional' materials A/C grade
spruce & plywood, so without asking him, don't know why it's got the
condition Chris was talking about, especially since he's just got a tail
skid (no wheel) & that keeps the back end weight down some too. I don't
recall seeing a chunk of lead on the motor mount when it was torn down for
it's annual last Spring, but then I wasn't looking for one either!
I'm not as worried about this so much on mine (yet!), since with the
Corvair I'll have a chunk of lead up front by necessity - it's called a
battery:).
Regards,
Kip Gardner
North Canton, OH
Message 20
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: del magsam <farmerdel@rocketmail.com>
--- John Dilatush <dilatush@amigo.net> wrote:
> --> Pietenpol-List message posted by: "John
> Dilatush" <dilatush@amigo.net>
>
>
> ----- Original Message -----
> From: "Christian Bobka" <bobka@charter.net>
> To: <pietenpol-list@matronics.com>
> Subject: RE: Pietenpol-List: Landing Gear Placement
> ++++++++++++++++++++
> Chris,
>
> Good explanation, you are absolutely right! Piet
> builders should understand
> that wheel placement is relative to the center of
> gravity of the entire mass
> and to use an arbitrary measurement such as
> "distance from the firewall" or
> "in front of the leading edge" are only asking for
> trouble.
>
> John
As long as I have everything built, I'll bolt it
together and see where I'm at. then change from there
if need be. I will be using a sonex style tailwheel
set up, which will cut weight by a good measure. and
aid in controllability.
thanks for the explanations.
Del
=====
Del-New Richmond, Wi
"farmerdel@rocketmail.com"
Message 21
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: Dmott9@aol.com
In a message dated 2/3/03 7:18:52 AM Eastern Standard Time,
dilatush@amigo.net writes:
> When it came to the placement of the gear, I figured that I wanted to have
> the ground contact of the wheels to be about 12 degrees forward of the CG.
> Turned out to be perfect. I can use the brakes pretty hard without any
> tendency to nose over, (the brakes are not that effective)yet it is light
> enough on the tailwheel, (12 lbs) to handle easily on the ground.
I am curious John, how did you arrive at the 12 degrees forward of the CG ?
Or is that 12 inches ?
-dennis
Message 22
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Landing Gear Placement |
--> Pietenpol-List message posted by: ZigoDan@aol.com
I owned a 1938 Aeronca chief at one time. The gear was far forward, to me it
made a forgiving aircraft, and I think one would have had to worked hard to
put it on the nose. The down side is it was hard to see out of when in the
three point attitude. You had to land with your peripheral vision when three
pointing. And it took a long time to get the nose up. But with the gear as
far forward it put a lot of weight on the tail, and made it feal more
positive to me. In retrospect my father-in-law has a Champ, and one day I
was by myself in the front seat, during the run up with brakes set I relaxed
the stick forward and almost put it on the nose, scared the crap out of me.
With my Chief and his Champ side by side you could really tell how far
forward the gear was on the Chief compared to his Champ.
And it seems to me when I used to build model RC planes putting the gear
farther forward help ground stability. Now I have not followed this
discussion that well but felt like telling you guys this just in case it
might help. If not nothing is lost.
DNA
Dan
Message 23
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
"Jim Skidmore" <jimskid@hotmail.com>, "Jim Markle" <Jim.Markle@primus.com>,
"Ron Oehler" <r.oehler@attbi.com>,
"Peter Denny" <peter.denny@mpls.k12.mn.us>,
"Pete Gavin" <petegavin@mn.rr.com>, "Pat Halligan" <pkhflying@aol.com>,
"Mike Dolan" <iamtopgun@voyager.net>, "Jeff Coffey" <coffey@crc-inc.com>,
"Greg Cardinal" <gcardinal@startribune.com>, "Frankh" <frankhanish@cs.com>,
"Ed Hansen" <DnEHansen@aol.com>, "David Kujawa" <dkujawa@cox.net>,
"Dan Carroll" <ecarroll@cpinternet.com>, "Chris Bobka" <bobka@charter.net>,
"Ron Hoyt" <rrhoyt@ieee.org>
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Pete,
Here it is. An attachment will come as well. I have pictures here at home
to personally deliver on tuesday evening.
Chris
BLAST IT! Part VIII
by Chris Bobka
This series was discontinued after the seventh installment when son number
two began to walk! That also coincided with David Kujawa leaving the
chapter newsletter editorship and taking over editorship of Sport Aerobatics
magazine and moving away to Arizona with his lovely wife, Diane. Instead of
looking forward to dropping off articles at David and Diane's and sharing a
few beers, I was frought with fear at having to bring articles to ugly Pete
and Bob. I hope you can find me some forgiveness for leaving you all
hanging. So sorry. Much prodding on the part of Pete, Greg, Frankh, and
others from the Pietenpol chat group has gotten me back to finishing off the
series with this final installment.
We left off with the gauntlets ready for installation to the front of the
box. I have included Figures 11 and 12 which show a cutting diagram for the
gauntlet and what the finished gauntlet should look like. As shown in
Figure 12, cut some darts into the big end of the gauntlet to help it lay
flat as shown in Figure 13. Put some caulk around the left opening in the
box and, using a heavy duty stapler, shoot some 1/4" staples into the box
around the circumference of the glove to hold it in place. Don't do what
Norm did so make sure you use the left handed gauntlet in the left hole of
the box and make sure you orient the thumb so that it is at about the 12
o'clock position. If you put the wrong gauntlet on that hole, you will have
to stand on the cieling in order to sandblast. Like Norm. Put more of the
caulk on top of the gauntlet and then take one of the rings from Figure 3
and and use enough 1-1/4" drywall screws to hold the gauntlet in place. You
can clean up any of the squeezed out caulk at this time. Install the other
glove. Thumbs up!
Next we need to install the door. You cut out the door opening in Figure 4
and at that time, I instructed you to save the cut out piece. Go get it.
Have an assistant hold the cut out piece in the door opening. Take two old
door hinges from the junk box and mark off the screw positions on the door
and on the frame to the rear of the door. Ensure that the hinge pins lie
directly over the cut line and the hinge lines are in line with each other.
Now take the door piece and lay it onto another piece of plywood that is
bigger than it. Mark off the same general shape but about 1-1/2 inches all
the way around it EXCEPT for the rear edge. This mark off should be even
with the rear edge of the door so the door can swing open.
What we are making here is a piece of plywood that will overlap the door
jamb so as to contain the direct blast of the sand. With your radial saw,
cut out the new piece. As the hinges on the door must lay in the same plane
as the box, it will be necessary to make cutouts to allow this new piece to
clear the door. Cut these out with a sabre saw. The top and side views of
Figure 14 clearly show this. You may design a better way and I know that
there are better ways but this is the way I did it. Go for it! Make the
latch as shown in Figure 14 from some scrap plywood. Attach the door and
latch to the box. If you want, you can get some felt weatherstripping about
1/8" thick and 1/2-3/4" wide and put it around the door jamb as indicated to
help contain some of the sand. An 1/8" looks thick but it will compress
right down.
Well that is it. The box is done. Now we have to come up with the gun.
You want a good one. The reason is that the gun uses air that passes
through a venturi in the gun to create suction which pulls the sand up from
the hopper, through the feed tube, and through the venturi itself,
accelerating the sand along the way. At the venturi, the sand makes a sharp
turn before it exits the nozzle. My dad, the physicist, says that force
times mass equals impact. We want impact as that is what does the
sandblasting. Mass is related to the the size and density of the particle.
Force is the effectiveness of the gun at accelerating the particle. Every
particle of sand that comes out of the gun also is trying to wear down the
venturi of the gun. A cheap ceramic nozzle coupled with a soft steel
venturi will not last long as the sand will abrade it right down and the
venturi will no longer be properly shaped to create a quality vacuum (if a
vacuum sucks, is it good or bad?). Lots of air will come out of the nozzle
but no abrasive. Then you will blame me that the sandblaster does not work.
We need space age materials. We need titanium. We need carbide.
So I will tell you what gun to get. It is shown in Figure 15. It is
available at Grainger, among other places, and can be found on the internet
as of February 2003 at:
http://www.grainger.com/Grainger/catalogpageview.jsp?xi=xi&CatPage=1427
You want model 3JT01 for the 12 CFM model. It lists for a wopping 77
dollars but buddy Jim Markle at jim_markle@mindspring.com has agreed to
purchase these guns from Grainger at his substantial discount and have them
drop shipped to interested buyers. The best thing is that parts are
available too as listed on the same web page. The gun does not have a
trigger. You do not want a gun with a trigger. A gun with a trigger takes
up too much room and your finger gets tired holding the trigger. Instead of
a trigger, I merely connect and disconnect a Milton coupling right at the
aft end of the gun. You could get fancy and use a foot pedal air switch or
you could put a valve at the point where the air line goes into the box.
Use what you think you would like.
Once you have your gun, attach it to the end of the pickup tube inside the
box with an appropriate length of 5/8" ID cheap clear vinyl tubing from the
big rack of tubing at Home Depot that I told you to get earlier. Use some
hose clamps to hold the hose on at both ends. Drill the smallest size hole
you can get away with to let the air line into the box. It should be
located near where the pickup tube is located so that both hoses can flop
around more or less together.
You need a vacuum cleaner of the big shop vac variety. This is a necessity
as you are creating a mammoth sandstorm inside the box. Without a shop vac,
it will be so cloudy inside the box after a minute that you won't be able to
see your hand in front of your face. You are pumping air into the box at 100
PSI and at 11-15 Cubic Feet per Minute. All the air has to go somewhere. If
there is no shop vac then this air will blow out through every seam and put
dust all over the garage and make a big mess. It will also go into your
lungs and you will contract silicosis and die a horrible slow death. The key
is to create a negative pressure inside the box so that the dust is trapped
by the filter of the shop vac. Better yet, use an extra long vacuum hose
and put the shop vac outside as even the filter on the shop vac won't trap
all the fines.
Their are endless varieties of abrasives to use. I use number five white
silica sand. You can remember number five as that is how many fingers you
should have on one of your hands. It is the same stuff that you see in sand
filled ashtrays next to the door to elevators in office buildings. Many
sandblasting supply outfits are reluctant to sell you sand for sandblasting
beacuse they are afraid you will not be using proper breathing protection
and they will be sued by your hiers after you die of silicosis. If you tell
them it is for ashtrays, then they will chum right up and gladly sell it to
you. It will come in 50 or 100 lb sacks. 100 lbs should do for starters.
Dick Navratril, a Pietenpol builder here in the Twin Cities area
(horzpool@goldengate.net), says you could also try a larger swimming pool
dealer to get sand. In his swimming pool supply shop, he carries red flint
granite sand sized at .45-.55 mm. It is rather aggressive but doesn't dust
nearly as much as white silica sands. Some may try to use glass beads or
walnut shells. It all depends upon the finish you wish, the aggressiveness
of the cleaning, and the price you are willing to pay.
You may consider building more than one sandblasting box. Each can have a
different abrasive. It is difficult to change abrasives from big to little
for the following reason: you will probably never get all the big stuff
out. What will happen is that you will make a change from big particles to
little particles. You will think you have it licked and you will be
blasting away looking at the fine, uniform finish on your blasted piece.
Just as the ten millionth particle comes out of the nozzle, a stray big
particle will come out, and whamo! there appears what will looks like a huge
crater in your work as that single particle hits. It may not bother you and
it may not matter based on the part you are blasting but sometime it may
matter. Again, the choice is yours. Once my new hangar is done, it will
sport a couple of blasting boxes each with a different abrasive.
Additonal abrasives management discussion is outside the scope of this
article. I am sure that industrious users of their new blast cabinet will
seek out information on http://www.google.com for more information.
A few tips on use are in order. All the debris you blast off of the pieces
you are sandblasting will fall down into the sand. Eventually, they will
migrate to the bottom of the hopper as it becomes their "turn" to be sucked
into the pickup tube. Large pieces of debris will clog the venturi of the
gun. The short term fix is to hold your free hand over the discharge nozzle
of the gun, forcing the compressed air down the hose abrasive supply hose
and the pickup tube and blowing all the junk out. This will work for a
while but sooner or later you will have to empty the abrasive out the bottom
of the hopper and sift it. I use a big sifter from the cookingware aisle of
the supermarket that looks like a bowl made out of screening. This is the
long term fix.
Use a pair of pliers kept in the box to hold small parts so you are not
always blasting away at the fingertips of your gloves as you hold parts.
The box makes for really good storage of parts that must be kept rust free.
The large quantity of sand acts as a dessicant to keep the air in the box
dry.
You can also experiment with different air pressures. 50-60 PSI works good
for most work. It is hard for many air compressors to keep this up at 12
CFM so from time to time you need to give the air compressor a chance to
catch up. Also, most air compressors have a duty cycle which means that it
is expected that a certain percentage of the time, the air compressor should
be off and resting. It cools when it rests. You may consider a
supplemental fan blowing on your air compressor to keep it cool.
Do not take stuff out of the blaster unless you have gloves on. The pros
say to use surgical gloves. Oils and acids from your skin will cause the
part to rust, even under paint.
As stressed in the beginning of this series of articles, moisture is the
bane of all sandblasters. you must have adequate moisture control in your
system. The ideal air supply system uses many feet of metal, not plastic or
rubber, air line between the compressor and the sandblaster. The metal
absorbs the heat from the compressed air. As the compressed air cools, the
water in it will condense out and deposit, in the form of water droplets,
onto the inside surface of the cool pipe. As the air passes through the
pipe it will roll these droplets along until they hit a moisture trap that
will inertially snag them and keep them from traveling further. It is
important to note that moisture traps trap water droplets, not water vapor.
Putting a mositure trap at the compressor outlet will not do much good since
the air will carry mostly vapor here as the air is so hot. The best "final"
moisture trap I know of is the 1/2" coalescing air filter as illustrated in
Figure 16 and sold by Tip Sandblasting at 1-800-321-9260. It uses a roll of
toilet paper inside the unit to absorb all remaining mositure after the air
has traveled through the standard inertial moisture traps of your system.
The price is up there on this unit bust the performance is spectacular.
Finally, as you sandblast and between sips of Guiness, USE PROTECTIVE
BREATHING EQUIPMENT APPROPRIATE FOR SANDBLASTING. If it is good for wearing
while doing drywall work, it should be good for sandblasting but read the
labels on the devices you might want to use! Also, use hearing protection
if you have the shop vac next to you. Ideally you can use a Walkman and its
little earplug type earpieces under your hearing protectors so you can
listen to the Grateful Dead as you blast away.
Good luck with your new unit and try to imagine how life was before you had
it!
Message 24
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | I added this too |
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Jim et al,
I forgot to add this as the second to last paragraph:
Jim Markle has posted ten pictures of his box on a website for viewing:
http://www.shutterfly.com/osi.jsp?i=67b0de21b3322ee6e4b7
thanks.
Chris
Message 25
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Ron skip and John |
--> Pietenpol-List message posted by: "Christian Bobka" <bobka@charter.net>
Ron butcher, Skip Gadd, and John Dilatush,
I am working this evening on finishing up the end of the sandblaster
articles and putting all the drawings in useable format for your use.
Please bear with me. I will have the stuff in the mail by next monday.
Thanks for your patience.
Chris
Message 26
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Question about Gross Weight |
--> Pietenpol-List message posted by: clif <cdawson5854@shaw.ca>
I have a formula for " minimum safe horsepower"
around here somewhere. I believe it's based on
the minimum hp that will provide a climb of 300 ft/min.
The ford A hp comes out right at that figure. So
my assumption has been that the power available
was the original bases for Bernards choice of gross
weight. Now that we have more powerful engines
in use the gross wt can be optimized for other
parameters, with safety in mind, of course. As Jack
has pointed out we must be carefull in our assumptions.
One question is how come the new plans come with
a 3/4" spar when the original was 1"? Who determined
that this is safe? Who performed the necessary
calculations? Where can we see these and what
design load was used? What are the permissable
G loads with this spar?
The answers are important to us now that we have
overcome the original power limitations.
Clif.
----- Original Message -----
From: "Jack Phillips" <jackphillips@earthlink.net>
Subject: RE: Pietenpol-List: Question about Gross Weight
> --> Pietenpol-List message posted by: "Jack Phillips"
<jackphillips@earthlink.net>
>
> Jon,
>
> Chris is right, up to a point. The gross weight is basically set by some
> structural parameter in the aircraft, usually the wing spar or the landing
> gear. You hear of a plane being stressed to +/- 10 G's, well that means
> the structure can handle a certain limit load, and depending on how many
G's
> the designer wants the plane to be good for, he divides the limit load by
> that number of G's and voila - the gross weight pops out!
>
> When I was a young engineer just out of college and was working for
General
> Dynamics on the F-16 initial design (sad that a plane designed in 1975 is
> still one of our front line fighters), the initial gross weight of the
plane
> was 23,000 lbs. (which meant it could go supersonic straight up with its
> 25,000 lb. thrust engine). Later, some mods to the landing gear enabled
it
> to takeoff with more fuel on board in external tanks and the takeoff gross
> weight was increased to 37,000 lbs, but its maneuvering gross weight was
> still 23,000.
>
> In other words, the gross weight is somewhat arbitrary. However, be aware
> that stall speed is a variable and goes up with gross weight. It is quite
> possible with a robust structured airplane to have a gross weight that is
> structurally safe but simply can't fly because the stall speed is too
high.
>
> For my Pietenpol, I've figured on a gross weight of around 1100 lbs.
>
> Jack
>
> -----Original Message-----
> From: owner-pietenpol-list-server@matronics.com
> [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Christian
> Bobka
> Sent: Sunday, February 02, 2003 11:36 PM
> To: pietenpol-list@matronics.com
> Subject: RE: Pietenpol-List: Question about Gross Weight
>
> --> Pietenpol-List message posted by: "Christian Bobka"
<bobka@charter.net>
>
> Jon,
>
> For an experimental, it is whatever you want it to be. Believe it or not.
> You set the rules. No kidding.
>
> Chris Bobka
>
> -----Original Message-----
> From: owner-pietenpol-list-server@matronics.com
> [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jon
> Botsford
> To: pietenpol-list@matronics.com
> Subject: Pietenpol-List: Question about Gross Weight
>
>
> --> Pietenpol-List message posted by: "Jon Botsford"
<botsford7@hot.rr.com>
>
> Can someone on this list tell me how the Gross Weight is calculated for an
> aircraft?
>
> Jon Botsford
>
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|