Today's Message Index:
----------------------
1. 04:15 AM - Re: Re: Glide speed and carrier approaches ()
2. 05:35 AM - Re: Fw: L/D redux (Roger Kemp M.D.)
3. 06:44 AM - Palatka Hanger (hkgibby@yahoo.com)
4. 09:20 AM - Re: Re: Glide speed and carrier approaches (Brian Lloyd)
5. 09:34 AM - Re: Fw: L/D redux (Brian Lloyd)
6. 10:21 AM - Re: Fw: L/D redux (Jerry Painter)
7. 11:45 AM - L/D again (Jerry Painter)
8. 12:08 PM - All Red Star (num1pilot@aol.com)
9. 01:46 PM - Re: Re: Glide speed and carrier approaches (Budd Davisson)
10. 02:20 PM - Re: L/D again (Budd Davisson)
11. 02:37 PM - Re: Re: Glide speed and carrier approaches ()
12. 02:38 PM - Yak 52 crash near Camas, Washington. Two fatals. (Hal)
13. 02:45 PM - Re: Fw: L/D redux (Roger Kemp M.D.)
14. 02:50 PM - Downed Yak 52 - more info (Hal)
15. 03:18 PM - Re: Downed Yak 52 - more info (Roger Kemp M.D.)
16. 04:08 PM - Re: Yak 52 crash near Camas, Washington. Two fatals. ()
17. 06:12 PM - Re: L/D again (Brian Lloyd)
18. 06:19 PM - Re: L/D again (Budd Davisson)
19. 07:17 PM - "Over Square, back loading, detuning, underboost-etc. (cjpilot710@aol.com)
20. 07:58 PM - Re: Fw: L/D redux (Walter Lannon)
21. 08:50 PM - Re: "Over Square, back loading, detuning, underboost-etc. (Roger Kemp M.D.)
22. 09:19 PM - Re: "Over Square, back loading, detuning, underboost-etc. (xiaobao)
Message 1
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| Subject: | Re: Glide speed and carrier approaches |
No, no. Sorry if I was confusing. They did perform the power off landings
but they were never taught to keep the airplane close enough to glide to the
runway power off at all times. Wasn't even mentioned in their training.
S
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Brian Lloyd
Sent: Friday, May 02, 2008 7:21 PM
Subject: Re: Yak-List: Re: Glide speed and carrier approaches
On May 2, 2008, at 11:23 AM, <scott.glaser@thedefiantcompany.com> wrote:
>
> I recently had some friends going for their PPL and we had a similar
> discussion regarding traffic patterns. When I was learning my
> instructor
> bordered on being physically abusive if I was not within gliding
> distance of
> the runway anytime after being established on downwind. Several of my
> friends who are currently working on or have recently received their
> PPL
> looked at me with a blank stare when I asked about this technique.
> Awareness of engine out gliding distance in the pattern wasn't even
> taught.
That is *REALLY* odd because a power-off spot landing from downwind is
a REQUIRED maneuver for PPL. (+200'/-0' from designated touch-down
point.)
> They did of course practice engine outs but that was merely practice
> for off
> field situation. They said their instruction was focused on quality
> of
> their pattern and setting up their approach. It was taught very
> much from
> the airline pilot perspective. It was kind of disturbing if you ask
> me, but
> then again it's not how I was raised.
That was true for a long time but the FAA has brought this home with
the required demonstration of the power-off spot landing. I let my CFI
lapse two years ago and had to take a check-ride again. The DE was a
stickler on this as it had just recently been added to the list of
required maneuvers. As a CFI one must demonstrate this to CL
proficiency, i.e. +100'/-0' from the designated touchdown point.
Brian Lloyd 3191 Western Drive
brianl AT lloyd DOT com Cameron Park, CA 95682
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
Message 2
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Jerry,
I thought that by pushing the pitch to full forward on the prop at cruise
manifold setting ( 600-750-800) and then pulling the MAP back to use the
prop as a speed brake would put you at risk for over speeding the engine?
Now you have set up a situation where the prop is driving the engine not the
engine driving the prop. Correct me if I'm wrong.
The translated 1990 RU manual that I have says for approaches set the pitch
at 80% and 400 mmHG on the advance (MAP lever)for the 52. I generally fly
70% and 400 mmHg or less (MAP) in the 50 as needed. I know at times being at
say 70-80% and 750-800 mmHG chasing down someone (lead or an adversary) then
pulling the MAP lever to idle to avoid overshoot is like having a big speed
brake out there! The but is in the huge change in pitch of the engine. I
always wondered if I was overstressing the reduction gears or the shaft
itself. Honestly I would rather go idle boards (deploy the speed brakes)
than use my engine as the speed brake.
I know a couple of old 17 drivers along with a 47 driver and T-28
driver/maintenance officer at the airport. I will ask then their take today
at our fly-in. If the weather permits!
Doc
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Jerry Painter
Sent: Friday, May 02, 2008 12:26 PM
Subject: Yak-List: Fw: L/D redux
Re-formatted just in case. Take two.
-------Original Message-------
From: Jerry Painter
Subject: L/D redux
Another factor that can play a big role is that many M-14 powered aircraft
have MT, Whirlwind and other 3-blade props that become very effective
airbrakes when pushed to high rpm at low power. I was reminded of this
yesterday flying with Jim Bourke, owner of RC Groups.com, in his Yak-54
(formerly owned by Eric Beard and known on the airshow circuit as Russian
Thunder). It has an MT. Jim likes to fly a "high-speed" (200-225 kph or so,
all the way to flare), close-in pattern, giving him better visibility, then
as he begins to flare he simply pushes the prop up to high rpm, followed by
reduced throttle. It's like flying into a big bowl of mush. The airplane
screeches to a halt, squats and lands. I've occasionally used this technique
myself, traffic permitting. The huge drag of the prop gives huge control of
speed at a moment's notice. If nothing else its a fun technique and keeping
the speed up on final can only be a good thing safety-wise. Not exactly your
typical (though it could be, in fact not a bad idea) practice "emergency"
landing technique, high, fast and steep. Not sure about MT's, but Whirlwinds
go high pitch with lost oil pressure.
There aren't many geared flat (or round) engines around any more and I've
read about alleged problems pilots of geared T-Bones and Commanders had with
reverse-loading of their engines, though I'm not sure "reverse-loading" is
actually happening, and its very short term during flare in any case. Anyone
have anything to offer on the subject re M-14's? Facts, not conjecture and
old-wives tales, please. Some of you old bomber pilots must have some info
on Pratts and Wrights, no?
On another subject, the -54 has very pronounced roll-coupling with rudder,
even though the rudder tapers significantly, with most of the area down low.
Not having much experience with big-rudder-optimized-for-gyros aerobatic
airplanes (like "none"), I'm wondering whether this is common and if it may
have contributed to some of the -54 "odd quirks" and "killer" stories, in
that that one was apparently spun in in Alaska (I understand it was the only
other -54 in the US). I didn't get much chance to explore it and its (way)
beyond my skill set anyway, but its a bit surprising to have the airplane
roll opposite rudder input, I.e., skid right and the left wing drops a bunch
A big help for some tumbling maneuvers no doubt, but may make some typical
maneuvers (like say, slips) and, especially, recovery techniques a bit odd
if not plain inappropriate.
BTW, Eric and Bud Granley are the only people I've seen hover an airplane
(Bud in his -55, preferably while inverted, flying formation with a
helicopter at very, very low altitude), though it may be common now. Didn't
get a chance to try it myself, but would love to one fine day.
Jerry Painter
Wild Blue Aviation
425-876-0865
wild.blue@verizon.net
www.FlyWBA.com
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All,
Have a T-hanger available at 28J/Palatka, FL. Contact me offlist if interested.
Hoot
Sent via BlackBerry from T-Mobile
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| Subject: | Re: Glide speed and carrier approaches |
On May 3, 2008, at 4:12 AM, <scott.glaser@thedefiantcompany.com> <scott.glaser@thedefiantcompany.com
> wrote:
>
> No, no. Sorry if I was confusing. They did perform the power off
> landings
> but they were never taught to keep the airplane close enough to
> glide to the
> runway power off at all times. Wasn't even mentioned in their
> training.
Well, I think Jerry had it right. In the course of a flight you are
rarely within gliding distance of a runway. And I did make the point
about the likelihood of engine failure vs. dealing with bozos in the
pattern. The incidence of bozos is much greater than the incidence of
engine failure so if you have an either/or situation you need to
accommodate the more likely scenario.
So maybe the right answer IS "fly the published pattern."
But I still prefer a continuous turn to final.
<sigh>
--
Brian Lloyd 3191 Western Drive
brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
Message 5
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| Subject: | Re: Fw: L/D redux |
On May 3, 2008, at 5:32 AM, Roger Kemp M.D. wrote:
> >
>
> Jerry,
> I thought that by pushing the pitch to full forward on the prop at
> cruise
> manifold setting ( 600-750-800) and then pulling the MAP back to use
> the
> prop as a speed brake would put you at risk for over speeding the
> engine?
Not if your prop governor is working properly.
> Now you have set up a situation where the prop is driving the engine
> not the
> engine driving the prop. Correct me if I'm wrong.
Yes, that is the case. But remember, when the RPM increases above the
set-point, the governor will drive the prop toward course pitch (lower
RPM). This reduces the angle-of-attack on the prop blades and they
will produce less lift (turning force). It is also why you get a
longer glide with the prop set to low RPM -- the prop is not taking as
much energy from the airframe to turn the engine.
> The translated 1990 RU manual that I have says for approaches set
> the pitch
> at 80% and 400 mmHG on the advance (MAP lever)for the 52. I
> generally fly
> 70% and 400 mmHg or less (MAP) in the 50 as needed. I know at times
> being at
> say 70-80% and 750-800 mmHG chasing down someone (lead or an
> adversary) then
> pulling the MAP lever to idle to avoid overshoot is like having a
> big speed
> brake out there! The but is in the huge change in pitch of the
> engine. I
> always wondered if I was overstressing the reduction gears or the
> shaft
> itself. Honestly I would rather go idle boards (deploy the speed
> brakes)
> than use my engine as the speed brake.
Well, think about it Roger. Do you think that the prop can generate
more torque turning the engine or the engine generate more torque
turning the prop? I think you will find that the torque is at its peak
when the engine is producing maximum power. That means that the
overall stresses on the gearbox will be less when the power is pulled
back.
> I know a couple of old 17 drivers along with a 47 driver and T-28
> driver/maintenance officer at the airport. I will ask then their
> take today
> at our fly-in. If the weather permits!
Now here is something you need to be careful about. You cannot assume
that the M14 or Huosai should be operated the same way that the big
Pratts and Wrights should be operated. As I understand it, the crank
on the Pratts and Wrights have just one oil journal and it feeds oil
to the contact point for the master rod bearing when the rod is
turning the crank. When the prop is turning the crank then the crank
is turning the master rod which changes the contact point. This can
lead to under-lubrication of the master rod bearing. That is why they
admonish you to never let the prop drive the engine in the Wrights and
Pratts.
So that brings up the question of how the M14 and Huosai engines get
oil to the master rod bearing. If there are oil journals to ensure
proper lubrication of the master rod bearing when the prop is turning
the engine then there is no reason to worry about doing damage to the
engine when you pull the throttle back to idle. Given that the M14 is
intended for aerobatic use, I suspect it *does* have proper
lubrication when the prop is driving the engine, hence the lack of an
warnings about the prop driving the engine in the manuals.
But this is only supposition on my part. Only someone who really knows
the engine can tell for sure.
--
Brian Lloyd 3191 Western Drive
brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
Message 6
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Message 7
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Budd--
You may not remember--be surprised if you did--but I flew with you a couple
of times maybe eight or ten years ago while I was visiting Phoenix one
winter--you had the M-14 in your hangar then. I'd never flown a Pitts,
wanted to do inverted and flat spins. We mostly shot landings and then you
sent me to Sonny Weller to do spins. Lots of fun. Then I read your story
about re-building your airplane (which you did shortly after we'd flown
together) and all the busted wood...ouch!
Anyway, I remember your engine failure(s) story and had fun doing VERY steep
slipping power-off approaches, but thought then, as I do now, that engine
failures in the pattern are no more likely than en route, except maybe on
first power reduction, so take your time about that and good luck on making
that 180, yes at 45 degrees bank. Maybe rope-break 180's at 200 feet are no
sweat in a glider, but they'll kill you in an airplane, any airplane.
Practice emergencies can be a good thing, but as I said to a student
yesterday as we watched an Apache do an engine-cut
shortly-after-breaking-ground climbout, sometimes practice can turn into the
real thing. Jab that jerk in the kidneys and tell him to keep his goddamned
hands off the controls until you're good and ready and not at 20 feet AGL
barely Vmc, thank you very much, simulated engine repair. I've had a few
exciting moments teaching engine-outs myself and was pleased as punch when
the feds decided maybe low-altitude power cuts at Vmc wasn't such a smart
thing to do. Lots of us Twin Comanche instructors and students and DPE's
were getting killed thinking they'd be pussycats like Apaches. But I
digress.
The manhole cover approach throws in a few semi-emergencies of its own, such
as giving you very little room for error on the slip recovery and runway
line-up. I much prefer a more normal, power-on (but still close-in), curved
or base and final approach with a little "peekaboo" let's-see-where-we
re-going-slip on final in any can't-see-where-you're-going airplane. Do you
(or anyone else) make steep, power-off, steep, slipping approaches SOP in
multi-engine airplanes? They're more subject to engine failures than
singles and lot more dangerous. Teaching primary students in a 172 is
interesting because they glide so well that even power-off you wind up
making a 747 approach, so might as well keep the power on (or off) and use
the flaps, even if the flight path is exactly the same. Granted, a 172 ain
t a Pitts ain't a T-6 ain't a Yak ain't a Lear, and L/D is a function of
many factors. Teaching folks how manipulate all of them at will to provide
desired performance and flight path makes a lot more sense to me than just
practicing engine-outs.
As always, there is lots of lamenting piloting skills and flight training
standards, but when most new and lots of "high-time" 500 hr. CFI's have
never flown anything but 172's and don't even know what a J-3 is, what do
you expect? Glass panels, IFR, FITS, 35-hour 141 programs, 20-hour LSP etc
are all wonderful things but ain't no substitute for basic airmanship.
Formation flying and aerobatics may be the best things ever happened to
flight training, mostly thanks to Yaks and RV's so far as I can tell. I don
t mean competition aerobatics, I mean sedate simple stuff. Precision
airmanship in all attitudes, airspeeds and configurations is what is
required. "My instructor told me" ain't airmanship and unfortunately the
scope of scenarios just keeps getting more and more complex. Nobody ever
learned to fly in 20 hours, or 35 or 40 or even 70 (though a much more
realistic figure).
Learn to control the airplane precisely under a variety of circumstances,
L/D configurations, speeds etc and emergencies will take care of themselves,
at the home drome, over mountains, desert or water. Yes, engine-out
practice helps, but most accidents happen while making plenty of power.
Let's be careful out there. Got a student waiting--gotta go.
Jerry Painter
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Air Boss
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?
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Message 9
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| Subject: | Re: Glide speed and carrier approaches |
Somewhere where between 2002 and 2005, the feds removed a paragraph from the
PPL PTS that said they had to set up the aircraft in such a way on approach
so as to always be within power-off gliding distance. I suspect they removed
it because it was in direct contradiction to their statements about
stabilized, power-on approaches in a later section.
On 5/3/08 9:18 AM, "Brian Lloyd" <brian-1927@lloyd.com> wrote:
>
>
> On May 3, 2008, at 4:12 AM, <scott.glaser@thedefiantcompany.com>
> <scott.glaser@thedefiantcompany.com
>> wrote:
>
>>
>> No, no. Sorry if I was confusing. They did perform the power off
>> landings
>> but they were never taught to keep the airplane close enough to
>> glide to the
>> runway power off at all times. Wasn't even mentioned in their
>> training.
>
> Well, I think Jerry had it right. In the course of a flight you are
> rarely within gliding distance of a runway. And I did make the point
> about the likelihood of engine failure vs. dealing with bozos in the
> pattern. The incidence of bozos is much greater than the incidence of
> engine failure so if you have an either/or situation you need to
> accommodate the more likely scenario.
>
> So maybe the right answer IS "fly the published pattern."
>
> But I still prefer a continuous turn to final.
>
> <sigh>
>
> --
> Brian Lloyd 3191 Western Drive
> brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> Antoine de Saint-Exupry
>
> PGP key ID: 12095C52A32A1B6C
> PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
>
>
>
>
>
>
>
>
Message 10
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See my notes in the body of your e-mail.
On 5/3/08 11:42 AM, "Jerry Painter" <wild.blue@verizon.net> wrote:
>
> Budd--
>
> You may not remember--be surprised if you did--but I flew with you a couple
> of times maybe eight or ten years ago while I was visiting Phoenix one
> winter--you had the M-14 in your hangar then. I'd never flown a Pitts,
> wanted to do inverted and flat spins. We mostly shot landings and then you
> sent me to Sonny Weller to do spins. Lots of fun. Then I read your story
> about re-building your airplane (which you did shortly after we'd flown
> together) and all the busted wood...ouch!
Actually, I remember flying with you quite well.
>
> Anyway, I remember your engine failure(s) story and had fun doing VERY steep
> slipping power-off approaches, but thought then, as I do now, that engine
> failures in the pattern are no more likely than en route, except maybe on
> first power reduction, so take your time about that and good luck on making
> that 180, yes at 45 degrees bank. Maybe rope-break 180's at 200 feet are no
> sweat in a glider, but they'll kill you in an airplane, any airplane.
> Practice emergencies can be a good thing, but as I said to a student
> yesterday as we watched an Apache do an engine-cut
> shortly-after-breaking-ground climbout, sometimes practice can turn into the
> real thing. Jab that jerk in the kidneys and tell him to keep his goddamned
> hands off the controls until you're good and ready and not at 20 feet AGL
> barely Vmc, thank you very much, simulated engine repair. I've had a few
> exciting moments teaching engine-outs myself and was pleased as punch when
> the feds decided maybe low-altitude power cuts at Vmc wasn't such a smart
> thing to do. Lots of us Twin Comanche instructors and students and DPE's
> were getting killed thinking they'd be pussycats like Apaches. But I
> digress.
You missed the point I was making: we're not training for failures in the
pattern. We're training for engine loss anywhere in the air. If you loose an
engine anywhere, on cross country, etc., and you've been doing nothing but
power on landings, then the last part of that particular episode will be an
experiment on your part because you don't have your power-off visual
references firmly in mind. If you're at 5,000 feet and the engine packs up,
then everything from that point on, should be an exercise in trying to get
the airplane down to a "normal" point adjacent to a viable landing spot and
the rest will be a normal power off landing. I strive to make the last
300-400 feet of every approach identical so there is a "bubble" of the end
of the most viable landing spot in which you'll be in a known landing
configuration, including speed, height, etc. AND you know you're going to
make the field because your previous experience with power on approaches has
given you that judgment.
>
> The manhole cover approach throws in a few semi-emergencies of its own, such
> as giving you very little room for error on the slip recovery and runway
> line-up.
If that's what you're experiencing, then you didn't pick up on what we were
doing in the Pitts. The approach includes a huge amount of ability to fine
tune the touchdown point because you're NOT pushing the approach to the
limits in terms of either height or line-up time. After you've seen it a few
times, you realize it just "looks" fast, but actually gives plenty of time.
And, we don't do it on every single landing. Operating off of what is
supposed to be the busiest single runway airport in the nation (according to
the Scottsdale PR people) means that less than 30% of our landings are power
off.
I much prefer a more normal, power-on (but still close-in), curved
> or base and final approach with a little "peekaboo" let's-see-where-we
> re-going-slip on final in any can't-see-where-you're-going airplane.
The slip isn't there to give visibility. Visibility comes from the offset
geometry of the approach which is apropos for blind airplanes only (doesn't
apply to CJs, etc). The sole purpose of the slip is to fine tune the
glideslope to the touchdown point from a point on final when there is
absolutely no doubt you're going to make the runway or the emergency
touchdown point. The purpose of doing enough power off approaches to be
comfortable with them is to know where the I'm-guaranteed-to-make-it point
is. If power-on approaches are habitually used, the pilot doesn't know
exactly how to orchestrate his arrival at that point, if the engine quits.
Do you
> (or anyone else) make steep, power-off, steep, slipping approaches SOP in
> multi-engine airplanes? They're more subject to engine failures than
> singles and lot more dangerous.
Go back to my original e-mail: I said power-off in airplanes which can be
landed power off. Although, in theory every airplane can be landed power off
(that's why every military pilot knows the "high key" of every airplane he
flies), for some, the combination of weight, engine type, etc., makes
power-off landings inadvisable. All of my discussions are limited to light
aircraft and the occasional power-off landing in aircraft like CJ's, etc.
Teaching primary students in a 172 is
> interesting because they glide so well that even power-off you wind up
> making a 747 approach, so might as well keep the power on (or off) and use
> the flaps, even if the flight path is exactly the same. Granted, a 172 ain
> t a Pitts ain't a T-6 ain't a Yak ain't a Lear, and L/D is a function of
> many factors. Teaching folks how manipulate all of them at will to provide
> desired performance and flight path makes a lot more sense to me than just
> practicing engine-outs.
I didn't say "just" practicing engine outs. I said doing them enough that
you develop the references. It's just another tool in the pilot's tool box,
just as every approach isn't slipped. It's just a fine tuning tool used to
put an airplane right on the point, when it's needed. And I agree, a pilot
needs to know all the possible ways to put an airplane exactly where it
needs to go in all conditions. Including with and without an engine. Now,
stand on the end of the runway and count the number of 172s you see land
that don't use power during the approach. If you need more than one or two
fingers, I'll be surprised. For two to four hours a day I'm watching them
and the good part about most of their approaches is that if they do manage
to have an engine failure, they won't shut the airport down because they'll
be so far off of airport property.
>
> As always, there is lots of lamenting piloting skills and flight training
> standards, but when most new and lots of "high-time" 500 hr. CFI's have
> never flown anything but 172's and don't even know what a J-3 is, what do
> you expect? Glass panels, IFR, FITS, 35-hour 141 programs, 20-hour LSP etc
> are all wonderful things but ain't no substitute for basic airmanship.
> Formation flying and aerobatics may be the best things ever happened to
> flight training, mostly thanks to Yaks and RV's so far as I can tell. I don
> t mean competition aerobatics, I mean sedate simple stuff. Precision
> airmanship in all attitudes, airspeeds and configurations is what is
> required. "My instructor told me" ain't airmanship and unfortunately the
> scope of scenarios just keeps getting more and more complex. Nobody ever
> learned to fly in 20 hours, or 35 or 40 or even 70 (though a much more
> realistic figure).
>
> Learn to control the airplane precisely under a variety of circumstances,
> L/D configurations, speeds etc and emergencies will take care of themselves,
> at the home drome, over mountains, desert or water. Yes, engine-out
> practice helps, but most accidents happen while making plenty of power.
>
I agree with the entire last paragraph.
> Let's be careful out there. Got a student waiting--gotta go.
>
> Jerry Painter
>
>
>
>
Message 11
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| Subject: | Re: Glide speed and carrier approaches |
Box pattern or continuous turn question aside, back in the day they trained
you to fly a stabilized approach and still be able to make the runway. A
homebuilt pilot found out the ramifications of being too far out at
Rosamond, CA last year. First flight of his homebuilt Zenith. He went for
a handful of power on base and didn't get it. He was too far out and hence
wound up on house roof .25 mile short of the runway (across the street from
my house). Granted this a bit of unusual situation in that it was
homebuilt's first flight but still, staying within gliding distance and
maintaining the pattern seem like a doable things considering the
consequences.
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Budd Davisson
Sent: Saturday, May 03, 2008 4:44 PM
Subject: Re: Yak-List: Re: Glide speed and carrier approaches
Somewhere where between 2002 and 2005, the feds removed a paragraph from the
PPL PTS that said they had to set up the aircraft in such a way on approach
so as to always be within power-off gliding distance. I suspect they removed
it because it was in direct contradiction to their statements about
stabilized, power-on approaches in a later section.
On 5/3/08 9:18 AM, "Brian Lloyd" <brian-1927@lloyd.com> wrote:
>
>
> On May 3, 2008, at 4:12 AM, <scott.glaser@thedefiantcompany.com>
> <scott.glaser@thedefiantcompany.com
>> wrote:
>
>>
>> No, no. Sorry if I was confusing. They did perform the power off
>> landings
>> but they were never taught to keep the airplane close enough to
>> glide to the
>> runway power off at all times. Wasn't even mentioned in their
>> training.
>
> Well, I think Jerry had it right. In the course of a flight you are
> rarely within gliding distance of a runway. And I did make the point
> about the likelihood of engine failure vs. dealing with bozos in the
> pattern. The incidence of bozos is much greater than the incidence of
> engine failure so if you have an either/or situation you need to
> accommodate the more likely scenario.
>
> So maybe the right answer IS "fly the published pattern."
>
> But I still prefer a continuous turn to final.
>
> <sigh>
>
> --
> Brian Lloyd 3191 Western Drive
> brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> Antoine de Saint-Exupry
>
> PGP key ID: 12095C52A32A1B6C
> PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
>
>
>
>
>
>
>
>
Message 12
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| Subject: | Yak 52 crash near Camas, Washington. Two fatals. |
A friend of mine, Ben Runyan, and his son were lost yesterday when his Yak
52 crashed. I do not have details yet.
Ben was a retired airline pilot, I believe with Delta.
I'll post more when there is more than rumors known.
Hal Morley
Message 13
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Brian,
Thanks for enlightening me. I was not thinking about the direct drive of the
P&Ws verses the geared drive of the M-14. Don't quote me but I believe the
M-14 master crank rod bearing has its own oil journal. I ran across that as
I was researching the oil supply of the prop governor for an engine
vibration occurring right at Vref.
It can be found in the diagrams of the M-14 engine manual.
Doc
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Brian Lloyd
Sent: Saturday, May 03, 2008 11:32 AM
Subject: Re: Yak-List: Fw: L/D redux
On May 3, 2008, at 5:32 AM, Roger Kemp M.D. wrote:
> >
>
> Jerry,
> I thought that by pushing the pitch to full forward on the prop at
> cruise
> manifold setting ( 600-750-800) and then pulling the MAP back to use
> the
> prop as a speed brake would put you at risk for over speeding the
> engine?
Not if your prop governor is working properly.
> Now you have set up a situation where the prop is driving the engine
> not the
> engine driving the prop. Correct me if I'm wrong.
Yes, that is the case. But remember, when the RPM increases above the
set-point, the governor will drive the prop toward course pitch (lower
RPM). This reduces the angle-of-attack on the prop blades and they
will produce less lift (turning force). It is also why you get a
longer glide with the prop set to low RPM -- the prop is not taking as
much energy from the airframe to turn the engine.
> The translated 1990 RU manual that I have says for approaches set
> the pitch
> at 80% and 400 mmHG on the advance (MAP lever)for the 52. I
> generally fly
> 70% and 400 mmHg or less (MAP) in the 50 as needed. I know at times
> being at
> say 70-80% and 750-800 mmHG chasing down someone (lead or an
> adversary) then
> pulling the MAP lever to idle to avoid overshoot is like having a
> big speed
> brake out there! The but is in the huge change in pitch of the
> engine. I
> always wondered if I was overstressing the reduction gears or the
> shaft
> itself. Honestly I would rather go idle boards (deploy the speed
> brakes)
> than use my engine as the speed brake.
Well, think about it Roger. Do you think that the prop can generate
more torque turning the engine or the engine generate more torque
turning the prop? I think you will find that the torque is at its peak
when the engine is producing maximum power. That means that the
overall stresses on the gearbox will be less when the power is pulled
back.
> I know a couple of old 17 drivers along with a 47 driver and T-28
> driver/maintenance officer at the airport. I will ask then their
> take today
> at our fly-in. If the weather permits!
Now here is something you need to be careful about. You cannot assume
that the M14 or Huosai should be operated the same way that the big
Pratts and Wrights should be operated. As I understand it, the crank
on the Pratts and Wrights have just one oil journal and it feeds oil
to the contact point for the master rod bearing when the rod is
turning the crank. When the prop is turning the crank then the crank
is turning the master rod which changes the contact point. This can
lead to under-lubrication of the master rod bearing. That is why they
admonish you to never let the prop drive the engine in the Wrights and
Pratts.
So that brings up the question of how the M14 and Huosai engines get
oil to the master rod bearing. If there are oil journals to ensure
proper lubrication of the master rod bearing when the prop is turning
the engine then there is no reason to worry about doing damage to the
engine when you pull the throttle back to idle. Given that the M14 is
intended for aerobatic use, I suspect it *does* have proper
lubrication when the prop is driving the engine, hence the lack of an
warnings about the prop driving the engine in the manuals.
But this is only supposition on my part. Only someone who really knows
the engine can tell for sure.
--
Brian Lloyd 3191 Western Drive
brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
Message 14
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| Subject: | Downed Yak 52 - more info |
Here is a link.
http://www.columbian.com/
Message 15
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| Subject: | Downed Yak 52 - more info |
A sad moment for all the YAK/CJ community. Please convey my/our condolences
to the family.
Please keep us informed as to the cause of the accident.
Roger "Doc" Kemp
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Hal
Sent: Saturday, May 03, 2008 4:47 PM
Subject: Yak-List: Downed Yak 52 - more info
Here is a link.
http://www.columbian.com/
Message 16
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| Subject: | Yak 52 crash near Camas, Washington. Two fatals. |
All are in our prayers.
http://www.kgw.com/news-local/stories/kgw_050208_news_plane_crash_clark_coun
ty.c1309437.html
S
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Hal
Sent: Saturday, May 03, 2008 5:36 PM
Subject: Yak-List: Yak 52 crash near Camas, Washington. Two fatals.
A friend of mine, Ben Runyan, and his son were lost yesterday when his Yak
52 crashed. I do not have details yet.
Ben was a retired airline pilot, I believe with Delta.
I'll post more when there is more than rumors known.
Hal Morley
Message 17
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On May 3, 2008, at 11:42 AM, Jerry Painter wrote:
> <wild.blue@verizon.net>
>
> Budd--
You think like me. You just don't piss other people off as much as I
do doing it. ;-)
Amen to everything you said.
--
Brian Lloyd 3191 Western Drive
brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
PGP key ID: 12095C52A32A1B6C
PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
Message 18
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If you only knew! :-)
On 5/3/08 5:13 PM, "Brian Lloyd" <brian-1927@lloyd.com> wrote:
>> Budd--
>
> You think like me. You just don't piss other people off as much as I
> do doing it. ;-)
>
> Amen to everything you said.
>
> --
> Brian Lloyd
Message 19
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| Subject: | "Over Square, back loading, detuning, underboost-etc. |
There has been several things mentioned here about the necessity or not of
staying "over square". Some are not quite sure at what is happening. I have
"lived" with this a good many years and I know that big radials will not last
long if you treat them poorly. In fact one of the reasons the bombers I fly
stay "in business" is because of the way we fly the engines. Averaging
around 300 plus hours a year per airplane - that's equates to about 600 takeoff
and landings a year per airplane. If we flew them the way the USAAF did, we'd
be changing engines every couple of months. Usually we change one engine
per year per airplane. Here is how the problem was written up in Warbird Notes
#3 in March 1994, by R.L. Sohn. It is probably the best explanation I've
ever seen written.
"Now the cause which we want discuss in this bulletin. This happens when
the pilot pulls the throttle back to a very low MP. --------- Under normal
conditions the master rod thrust bearing is loaded against the crankshaft from
multiplicity of direction as all the pistons progress through their assigned
firing order. Remember that all the other connecting rods are linked to this
one master rod and the pressures on this master rod journal are the constantly
changing resultant of all the pressures exerted by these pistons. The
crankshaft is drilled on the thrust side allowing oil access to this area when
under power. The heat is carried away with the oil flow. No oil hole is
drilled on the anti-thrust side, it's not considered necessary since the hole
the
thrust side provides constant lubrication from pressurized oil flowing around
the bearing. If this series of alternating forces is severely disturbed by a
large reduction in MP then the propeller in effect is turning the engine.
It might be helpful here to visualize the unloaded pistons trying to throw
themselves out the top of the cylinders. In this case the load is continuously
applied to this one (anti-thrust side) area of the master rod journal where
no oil hole is located. In short order this "squeeze play" situation causes
oil (lubrication and cooling ) starvation resulting in failure to dissipate
the frictional heat. This rapidly progresses from overheating to self
destruction. In some cases during tear down the bleed holes have been found wiped
full of silver metal from the multi-layered plating of the master rod bearing"
The Wright can stand up a little better the Pratts because the they have
more master rod bearing area. The journal diameter of the 1820 is about 3 1/4"
as compared to the 1830's 2 5/8". Both have virtually the same displacement.
Comparing the M-14? There no doubt that the forces and situation is the
same. However I do not know the oiling of the M-14. Jill could elucidate
better than I on that. I think if you compare engine size to horsepower (I don't
how to arthritically do that) I believe you'd find the M-14 is "beefier" for
its HP. I know that I fly my M14 the same way I do the Pratts and Wrights.
Jim "Pappy" Goolsby
**************Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
Message 20
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| Subject: | Re: Fw: L/D redux |
You all are getting me confused! High RPM, low MP, overspeed??, contact
points for the master rod bearing??, direct drive, geared drive. Where to
begin---------
At some point on approach you will reduce the power and, if you follow
standard practice, will move the prop control to High RPM. If you have
reduced power enough you will not see any RPM increase because the governor
has sensed an underspeed condition and has already moved the blades to full
fine.
The only reason for moving the prop control is to set up for a possible
emergency go-around.
Therefore the prop is always in the highest drag condition on a normal
landing.
There can be no "overspeed" since with increasing power the governor will
limit RPM to the max. setting. However, if you run significantly reduced
power at the max. RPM for any length of time there is the possibility of
damage due to the increased centrifugal loading of the piston and pin. That
is the primary reason for avoiding that scenario.
There is no such thing as a "contact point" on the master rod bearing,
unless it is totally worn out and nearing failure. That is the function of
oil. It's main purpose is to ensure there is NO contact.
The master rod bearing (and the inner bearing end of each link rod) is
pressure lubricated from the crank journal cavity on ALL radial engines.
Whether geared or direct drive makes zero difference in this area.
It is possible that the M14 is more tolerant of centrifugal piston loading
than P&W or Curtis Wright engines simply due to the small piston size.
Cheers;
Walt
----- Original Message -----
From: "Roger Kemp M.D." <viperdoc@mindspring.com>
Sent: Saturday, May 03, 2008 2:42 PM
Subject: RE: Yak-List: Fw: L/D redux
> <viperdoc@mindspring.com>
>
> Brian,
> Thanks for enlightening me. I was not thinking about the direct drive of
> the
> P&Ws verses the geared drive of the M-14. Don't quote me but I believe the
> M-14 master crank rod bearing has its own oil journal. I ran across that
> as
> I was researching the oil supply of the prop governor for an engine
> vibration occurring right at Vref.
> It can be found in the diagrams of the M-14 engine manual.
> Doc
>
> -----Original Message-----
> From: owner-yak-list-server@matronics.com
> [mailto:owner-yak-list-server@matronics.com] On Behalf Of Brian Lloyd
> Sent: Saturday, May 03, 2008 11:32 AM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Fw: L/D redux
>
>
>
> On May 3, 2008, at 5:32 AM, Roger Kemp M.D. wrote:
>
>> <viperdoc@mindspring.com
>
>> >
>>
>> Jerry,
>> I thought that by pushing the pitch to full forward on the prop at
>> cruise
>> manifold setting ( 600-750-800) and then pulling the MAP back to use
>> the
>> prop as a speed brake would put you at risk for over speeding the
>> engine?
>
> Not if your prop governor is working properly.
>
>> Now you have set up a situation where the prop is driving the engine
>> not the
>> engine driving the prop. Correct me if I'm wrong.
>
> Yes, that is the case. But remember, when the RPM increases above the
> set-point, the governor will drive the prop toward course pitch (lower
> RPM). This reduces the angle-of-attack on the prop blades and they
> will produce less lift (turning force). It is also why you get a
> longer glide with the prop set to low RPM -- the prop is not taking as
> much energy from the airframe to turn the engine.
>
>> The translated 1990 RU manual that I have says for approaches set
>> the pitch
>> at 80% and 400 mmHG on the advance (MAP lever)for the 52. I
>> generally fly
>> 70% and 400 mmHg or less (MAP) in the 50 as needed. I know at times
>> being at
>> say 70-80% and 750-800 mmHG chasing down someone (lead or an
>> adversary) then
>> pulling the MAP lever to idle to avoid overshoot is like having a
>> big speed
>> brake out there! The but is in the huge change in pitch of the
>> engine. I
>> always wondered if I was overstressing the reduction gears or the
>> shaft
>> itself. Honestly I would rather go idle boards (deploy the speed
>> brakes)
>> than use my engine as the speed brake.
>
> Well, think about it Roger. Do you think that the prop can generate
> more torque turning the engine or the engine generate more torque
> turning the prop? I think you will find that the torque is at its peak
> when the engine is producing maximum power. That means that the
> overall stresses on the gearbox will be less when the power is pulled
> back.
>
>> I know a couple of old 17 drivers along with a 47 driver and T-28
>> driver/maintenance officer at the airport. I will ask then their
>> take today
>> at our fly-in. If the weather permits!
>
> Now here is something you need to be careful about. You cannot assume
> that the M14 or Huosai should be operated the same way that the big
> Pratts and Wrights should be operated. As I understand it, the crank
> on the Pratts and Wrights have just one oil journal and it feeds oil
> to the contact point for the master rod bearing when the rod is
> turning the crank. When the prop is turning the crank then the crank
> is turning the master rod which changes the contact point. This can
> lead to under-lubrication of the master rod bearing. That is why they
> admonish you to never let the prop drive the engine in the Wrights and
> Pratts.
>
> So that brings up the question of how the M14 and Huosai engines get
> oil to the master rod bearing. If there are oil journals to ensure
> proper lubrication of the master rod bearing when the prop is turning
> the engine then there is no reason to worry about doing damage to the
> engine when you pull the throttle back to idle. Given that the M14 is
> intended for aerobatic use, I suspect it *does* have proper
> lubrication when the prop is driving the engine, hence the lack of an
> warnings about the prop driving the engine in the manuals.
>
> But this is only supposition on my part. Only someone who really knows
> the engine can tell for sure.
>
>
> --
> Brian Lloyd 3191 Western Drive
> brian HYPHEN 1927 AT lloyd DOT com Cameron Park, CA 95682
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> - Antoine de Saint-Exupry
>
> PGP key ID: 12095C52A32A1B6C
> PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C
>
>
>
Message 21
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| Subject: | "Over Square, back loading, detuning, underboost-etc. |
Pappy,
Thanks. So my theory according to this excerpt was correct in feeling
comfortable in pulling the MAP to idle with the %RPM pushed up.
Now I understand better what is really going on at the Master Rod main
bearing.
Doc
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of cjpilot710@aol.com
Sent: Saturday, May 03, 2008 9:14 PM
Subject: Yak-List: "Over Square, back loading, detuning, underboost-etc.
There has been several things mentioned here about the necessity or not of
staying "over square". Some are not quite sure at what is happening. I
have "lived" with this a good many years and I know that big radials will
not last long if you treat them poorly. In fact one of the reasons the
bombers I fly stay "in business" is because of the way we fly the engines.
Averaging around 300 plus hours a year per airplane - that's equates to
about 600 takeoff and landings a year per airplane. If we flew them the way
the USAAF did, we'd be changing engines every couple of months. Usually we
change one engine per year per airplane. Here is how the problem was
written up in Warbird Notes #3 in March 1994, by R.L. Sohn. It is probably
the best explanation I've ever seen written.
"Now the cause which we want discuss in this bulletin. This happens when
the pilot pulls the throttle back to a very low MP. --------- Under normal
conditions the master rod thrust bearing is loaded against the crankshaft
from multiplicity of direction as all the pistons progress through their
assigned firing order. Remember that all the other connecting rods are
linked to this one master rod and the pressures on this master rod journal
are the constantly changing resultant of all the pressures exerted by these
pistons. The crankshaft is drilled on the thrust side allowing oil access
to this area when under power. The heat is carried away with the oil flow.
No oil hole is drilled on the anti-thrust side, it's not considered
necessary since the hole the thrust side provides constant lubrication from
pressurized oil flowing around the bearing. If this series of alternating
forces is severely disturbed by a large reduction in MP then the propeller
in effect is turning the engine. It might be helpful here to visualize the
unloaded pistons trying to throw themselves out the top of the cylinders.
In this case the load is continuously applied to this one (anti-thrust side)
area of the master rod journal where no oil hole is located. In short order
this "squeeze play" situation causes oil (lubrication and cooling )
starvation resulting in failure to dissipate the frictional heat. This
rapidly progresses from overheating to self destruction. In some cases
during tear down the bleed holes have been found wiped full of silver metal
from the multi-layered plating of the master rod bearing"
The Wright can stand up a little better the Pratts because the they have
more master rod bearing area. The journal diameter of the 1820 is about 3
1/4" as compared to the 1830's 2 5/8". Both have virtually the same
displacement.
Comparing the M-14? There no doubt that the forces and situation is the
same. However I do not know the oiling of the M-14. Jill could elucidate
better than I on that. I think if you compare engine size to horsepower (I
don't how to arthritically do that) I believe you'd find the M-14 is
"beefier" for its HP. I know that I fly my M14 the same way I do the Pratts
and Wrights.
Jim "Pappy" Goolsby
_____
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Message 22
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| Subject: | "Over Square, back loading, detuning, underboost-etc. |
--- On Sat, 5/3/08, Roger Kemp M.D. <viperdoc@mindspring.com> wrote:
>> ... Now I understand better <<
Randy Sohn is surely one of the masters of the radial world, indeed, one of the
masters of the legacy aviation world.
There may be some reading this list who don't know his name. He's had a good bit
to say about flying and it can be a good idea to search out his comment.
best ...
jack
> From: Roger Kemp M.D. <viperdoc@mindspring.com>
> Subject: RE: Yak-List: "Over Square, back loading, detuning, underboost-etc.
> To: yak-list@matronics.com
> Date: Saturday, May 3, 2008, 11:47 PM
> Pappy,
>
> Thanks. So my theory according to this excerpt was correct
> in feeling
> comfortable in pulling the MAP to idle with the %RPM pushed
> up.
>
> Now I understand better what is really going on at the
> Master Rod main
> bearing.
>
> Doc
>
>
>
> From: owner-yak-list-server@matronics.com
> [mailto:owner-yak-list-server@matronics.com] On Behalf Of
> cjpilot710@aol.com
> Sent: Saturday, May 03, 2008 9:14 PM
> To: yak-list@matronics.com
> Subject: Yak-List: "Over Square, back loading,
> detuning, underboost-etc.
>
>
>
> There has been several things mentioned here about the
> necessity or not of
> staying "over square". Some are not quite sure
> at what is happening. I
> have "lived" with this a good many years and I
> know that big radials will
> not last long if you treat them poorly. In fact one of the
> reasons the
> bombers I fly stay "in business" is because of
> the way we fly the engines.
> Averaging around 300 plus hours a year per airplane -
> that's equates to
> about 600 takeoff and landings a year per airplane. If we
> flew them the way
> the USAAF did, we'd be changing engines every couple of
> months. Usually we
> change one engine per year per airplane. Here is how the
> problem was
> written up in Warbird Notes #3 in March 1994, by R.L. Sohn.
> It is probably
> the best explanation I've ever seen written.
>
>
>
>
>
> "Now the cause which we want discuss in this bulletin.
> This happens when
> the pilot pulls the throttle back to a very low MP.
> --------- Under normal
> conditions the master rod thrust bearing is loaded against
> the crankshaft
> from multiplicity of direction as all the pistons progress
> through their
> assigned firing order. Remember that all the other
> connecting rods are
> linked to this one master rod and the pressures on this
> master rod journal
> are the constantly changing resultant of all the pressures
> exerted by these
> pistons. The crankshaft is drilled on the thrust side
> allowing oil access
> to this area when under power. The heat is carried away
> with the oil flow.
> No oil hole is drilled on the anti-thrust side, it's
> not considered
> necessary since the hole the thrust side provides constant
> lubrication from
> pressurized oil flowing around the bearing. If this series
> of alternating
> forces is severely disturbed by a large reduction in MP
> then the propeller
> in effect is turning the engine. It might be helpful here
> to visualize the
> unloaded pistons trying to throw themselves out the top of
> the cylinders.
> In this case the load is continuously applied to this one
> (anti-thrust side)
> area of the master rod journal where no oil hole is
> located. In short order
> this "squeeze play" situation causes oil
> (lubrication and cooling )
> starvation resulting in failure to dissipate the frictional
> heat. This
> rapidly progresses from overheating to self destruction.
> In some cases
> during tear down the bleed holes have been found wiped full
> of silver metal
> from the multi-layered plating of the master rod
> bearing"
>
>
>
> The Wright can stand up a little better the Pratts because
> the they have
> more master rod bearing area. The journal diameter of the
> 1820 is about 3
> 1/4" as compared to the 1830's 2 5/8". Both
> have virtually the same
> displacement.
>
>
>
> Comparing the M-14? There no doubt that the forces and
> situation is the
> same. However I do not know the oiling of the M-14. Jill
> could elucidate
> better than I on that. I think if you compare engine size
> to horsepower (I
> don't how to arthritically do that) I believe you'd
> find the M-14 is
> "beefier" for its HP. I know that I fly my M14
> the same way I do the Pratts
> and Wrights.
>
>
>
> Jim "Pappy" Goolsby
>
>
>
>
>
> _____
>
> Wondering what's for Dinner Tonight? Get new
> <http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001>
> twists on
> family favorites at AOL Food.
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