Today's Message Index:
----------------------
1. 04:59 AM - Grumman strength (Bruce Smith)
2. 07:06 AM - Re: TeamGrumman-List Digest: 1 Msgs - 04/05/06 (airman@appledumplings.com)
3. 07:47 AM - Re: Re: TeamGrumman-List Digest: 1 Msgs - 04/05/06 (flyv35b)
4. 07:57 AM - Re: Grumman strength (flyv35b)
5. 08:44 AM - Re: Prop Pitch (923te)
6. 08:50 AM - Re: Prop Pitch (923te)
7. 01:34 PM - Re: Grumman strength (TeamGrumman@aol.com)
8. 01:47 PM - Grumman strength and anecdote. (TeamGrumman@AOL.COM)
9. 02:51 PM - Re: Grumman strength (923te)
10. 03:13 PM - Re: Grumman strength (flyv35b)
11. 04:01 PM - Re: Grumman strength (A1ynk@aol.com)
12. 04:35 PM - Re: Aileron Flexing (923te)
13. 09:48 PM - Re: Grumman strength (Gil Alexander)
14. 11:23 PM - Re: Aileron Flexing (TeamGrumman@AOL.COM)
15. 11:26 PM - Re: Grumman strength (TeamGrumman@AOL.COM)
16. 11:28 PM - Re: Grumman strength (TeamGrumman@AOL.COM)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Grumman strength |
--> TeamGrumman-List message posted by: Bruce Smith <bruce.smith@york.com>
Gary, and fellow Teammates,
What is it that goes into determining the Vne of an airplane? Is it
shear (brute?) strength alone, or aerodynamics, or a combination of
factors. The Cheetah I fly has a Vne of 190 mph, where a Piper Archer is
redlined at 174 mph.
Slow day again, so I thought I'd ask. Gary, any amusing annuals lately?
Thanks.
Bruce Smith
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: TeamGrumman-List Digest: 1 Msgs - 04/05/06 |
--> TeamGrumman-List message posted by: airman@appledumplings.com
I was wondering what most people thought on prop pitch. I am in the
process of buying a new prop for my new(for me) 1976 tiger.
I will be going into a fl field that is 2300 ' but i dont want to
totally sacrifice speed.
Thomas
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: | Re: TeamGrumman-List Digest: 1 Msgs - 04/05/06 |
--> TeamGrumman-List message posted by: "flyv35b" <flyv35b@ashcreekwireless.com>
I'd stay with the standard 63" pitch Sensenich unless you have a Power Flow
exhaust and are planning on some aerodynamic clean-up. This should allow
you to turn about 2700 rpm at full throttle at lower altitudes, which is
about what you want.
Cliff A&P/IA
----- Original Message -----
From: <airman@appledumplings.com>
Sent: Thursday, April 06, 2006 7:05 AM
Subject: TeamGrumman-List: Re: TeamGrumman-List Digest: 1 Msgs - 04/05/06
> --> TeamGrumman-List message posted by: airman@appledumplings.com
>
>
> I was wondering what most people thought on prop pitch. I am in the
> process of buying a new prop for my new(for me) 1976 tiger.
> I will be going into a fl field that is 2300 ' but i dont want to
> totally sacrifice speed.
>
> Thomas
>
>
>
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: Grumman strength |
--> TeamGrumman-List message posted by: "flyv35b" <flyv35b@ashcreekwireless.com>
Certified aircraft are required (FAR Part 23) to be dive tested (design dive
speed) to 10% above what the manufacture sets as Vne. For the Tiger that
would amount to about 220 mph. As far as I can determine this is and has
always been based on IAS. But read the article by Van's chief engineer
about their "theory" that Vne is and should be based on TAS. Quite
interesting but I don't know if this has been subscribed to in any
aerodynamic texts (Gary should be able to shed some light on this).
http://www.vansaircraft.com/pdf/hp_limts.pdf
This doesn't mean that flutter will automatically occur at the design dive
speed, just that the plane was tested up to that speed and the controls
excited and there wasn't any catastrophic flutter. But don't forget that
this was with a new plane with tight controls, cables adjust properly and no
wear in the trim linkage. And Lord knows I have seen a lot of Grummans with
quite a bit of elevator trim linkage, much more than a new plane would have.
Cliff A&P/IA
----- Original Message -----
From: "Bruce Smith" <bruce.smith@york.com>
Sent: Thursday, April 06, 2006 4:57 AM
Subject: TeamGrumman-List: Grumman strength
> --> TeamGrumman-List message posted by: Bruce Smith <bruce.smith@york.com>
>
> Gary, and fellow Teammates,
>
> What is it that goes into determining the Vne of an airplane? Is it
> shear (brute?) strength alone, or aerodynamics, or a combination of
> factors. The Cheetah I fly has a Vne of 190 mph, where a Piper Archer is
> redlined at 174 mph.
>
> Slow day again, so I thought I'd ask. Gary, any amusing annuals lately?
>
> Thanks.
>
> Bruce Smith
>
>
>
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 |
|
--> TeamGrumman-List message posted by: "923te" <923te@cox.net>
I agree with Cliff. A 63" pitch is what I had n my '76 Tiger and I never had
a problem on our 1800' strip, even when it was 105 in the summer. Field
elevation 1260'. I did also take off at 8000' and it took about 3000' of
runway at 85. If you have Powerflow and have had a port and flow match
done then you might consider a 65" pitch
Best Regards,
Ned
----- Original Message -----
From: <airman@appledumplings.com>
Sent: Thursday, April 06, 2006 9:05 AM
Subject: TeamGrumman-List: Re: TeamGrumman-List Digest: 1 Msgs - 04/05/06
> --> TeamGrumman-List message posted by: airman@appledumplings.com
>
>
> I was wondering what most people thought on prop pitch. I am in the
> process of buying a new prop for my new(for me) 1976 tiger.
> I will be going into a fl field that is 2300 ' but i dont want to
> totally sacrifice speed.
>
> Thomas
>
>
>
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 |
|
--> TeamGrumman-List message posted by: "923te" <923te@cox.net>
Better yet get an MT constant speed prop.
For pictures and performance comparison see:
http://members.cox.net/923te/Propellers%20Compared.htm
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: Grumman strength |
--> TeamGrumman-List message posted by: TeamGrumman@aol.com
In a message dated 4/6/06 7:57:57 AM, flyv35b@ashcreekwireless.com writes:
> This doesn't mean that flutter will automatically occur at the design dive
> speed, just that the plane was tested up to that speed and the controls
> excited and there wasn't any catastrophic flutter.=A0 But don't forget that
> this was with a new plane with tight controls, cables adjust properly and=20no
> wear in the trim linkage.=A0 And Lord knows I have seen a lot of Grummans=20with
> quite a bit of elevator trim linkage, much more than a new plane would have.
>
OFF-THE-RECORD: I know of one Cheetah that did a split-S at 12,000 feet and
leveled off at 3,000 feet. At or near 200 indicated for a good portion of
the way down. Smooth as silk.
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: | Grumman strength and anecdote. |
--> TeamGrumman-List message posted by: TeamGrumman@aol.com
In a message dated 4/6/06 5:00:25 AM, bruce.smith@york.com writes:
> Slow day again, so I thought I'd ask. Gary, any amusing annuals lately?
>
>
Cliff is right regarding the Vne using IAS. I've never seen a report saying
otherwise. The Q, dynamic loads, are based on density, rho. I can't see
where using TAS makes any sense. But, what doi I know.
I isntalled a PlanePwer alternator in a customers plane. It's a very pretty
alternator. Looks very professional. My only comment is that the Field and
Ground wire terminals are VERY close to the baffle. Be very careful here.
I think it would be worth making a two connector quick disconnect for these.
That way, you could make sure the connectors are covered while working on it
on the bench. Just a thought.
I'm doing a FWF on a Cheetah. The firewall is now all white, white powder
coated engine mount, and red powder coated cabin heat Y thingy - battery box -
bracket for the shock absorbers (on the nose gear) - and all of the throttle
cable support hardware. The Oil Cooler hardware is all powder coated silver.
The baffles are POWDER COATED in gray wrinkle.
After I stripped the entire firewall and brackets, and engine mounts (on the
airframe) I painted the entire firewall in white Imron. Then, I went over
and detailed things like the cabin heat control (which I did in Black splatter
paint), the engine mounts (which I painted over with green zinc chromate - just
for looks), the shock bracket mounted on the fuselage (which I painted over
with silver) and a few otehr odds and ends. It's all white Imron under neath,
just looks like I did it all separately.
This plane also got a JPI with Fuel Flow.
You don't even want to know what the bill its....
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: Grumman strength |
--> TeamGrumman-List message posted by: "923te" <923te@cox.net>
I thought you all might be interested in Fred Kokaska's comments when I ask
him a similar question concerning Vne for teh 540 powered Tigers:
Fred:
"I went through the Vne part of certification at 100% of Vne for an AA5B
(174 KIAS), There were two Part 23 objectives in this flight test (flown by
FAA test pilot) of verifying the prop does not overspeed (above 2700 RPM) at
Vne. .... The other was pitch and roll control and airframe vibration.
The test pilot started at 10 K feet and pushed over at full power to
establish 174 KIAS, did some 30 degree left and right rolling maneuvers. He
commented (and I looked out the right side) on the fact the ailerons were
both about 2 inches above the normal even with the flap position in level
flight from airloads. While this looks spooky, he noticed no binding or
control input problems that he did not like."
I think the aileron flexing is a bit unerving.
Best Regards,
Ned
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: | Re: Grumman strength |
--> TeamGrumman-List message posted by: "flyv35b" <flyv35b@ashcreekwireless.com>
> I think the aileron flexing is a bit unnerving.
> Best Regards,
> Ned
Apparently due to the high airflow over them and stretch of the cables or
deflection in the system. I guess that is the position they want to seek at
high airflow. Any flight at Vne can be a bit unnerving.
Cliff
----- Original Message -----
From: "923te" <923te@cox.net>
Sent: Thursday, April 06, 2006 2:50 PM
Subject: Re: TeamGrumman-List: Grumman strength
> --> TeamGrumman-List message posted by: "923te" <923te@cox.net>
>
> I thought you all might be interested in Fred Kokaska's comments when I
> ask
> him a similar question concerning Vne for teh 540 powered Tigers:
>
> Fred:
> "I went through the Vne part of certification at 100% of Vne for an AA5B
> (174 KIAS), There were two Part 23 objectives in this flight test (flown
> by
> FAA test pilot) of verifying the prop does not overspeed (above 2700 RPM)
> at
> Vne. .... The other was pitch and roll control and airframe vibration.
>
> The test pilot started at 10 K feet and pushed over at full power to
> establish 174 KIAS, did some 30 degree left and right rolling maneuvers.
> He
> commented (and I looked out the right side) on the fact the ailerons were
> both about 2 inches above the normal even with the flap position in level
> flight from airloads. While this looks spooky, he noticed no binding or
> control input problems that he did not like."
>
>
> I think the aileron flexing is a bit unerving.
> Best Regards,
> Ned
>
>
>
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: Grumman strength |
--> TeamGrumman-List message posted by: A1ynk@aol.com
The aileron flexing is in the torque tube. It is meant to flex. That is how
you get the 15 degrees up travel and 7.5 down. The aileron hits the stop and
then the torque tube flexes alowing the other aileron to go up and hit that stop.
Bill Hatton
N9965U
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: | Re: Aileron Flexing |
--> TeamGrumman-List message posted by: "923te" <923te@cox.net>
One of the aileron Torque tubes on my Saber Tooth has a little groove in it
and I wonder if it needs replaced???
The groove is about .5" Long by .25 wide and is .014 at its deepest point.
It is about 16" from the tube end.
I anticipate flying regularly in the yellow arc..should I be concerned about
the 2000+ and 30 years of sress that has already occurred on th torque tubes
and the impact of this small gouge?
I understand that the only spec we have on the torque tubes is for wear. A
max of 0.030" wear is acceptable, and that is measured as TOTAL wall
reduction, so its not 0.030" on each side of the tube.
Bill Hatten are you the one that used to care for this Cheetah? 9715U Keith
Fuller used to have?
What do you think Bill, Gary?
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: Grumman strength |
--> TeamGrumman-List message posted by: Gil Alexander <gilalex@earthlink.net>
Don't forget the one that had aileron flutter at Van Nuys....
The photo of the 'bent' wing was quite scary, but nice to see the spar
could bend without breaking.
They lost their counterweights in wake turbulence while on downwind.
It was on a FAA poster at WJF - I'm sure Gary remembers it.... I think it
got the aileron AD started....
gil in Tucson
At 01:31 PM 4/6/2006, you wrote:
>--> TeamGrumman-List message posted by: TeamGrumman@aol.com
>
>
>In a message dated 4/6/06 7:57:57 AM, flyv35b@ashcreekwireless.com writes:
>
>
> > This doesn't mean that flutter will automatically occur at the design dive
> > speed, just that the plane was tested up to that speed and the controls
> > excited and there wasn't any catastrophic flutter.=A0 But don't forget that
> > this was with a new plane with tight controls, cables adjust properly
> and=20no
> > wear in the trim linkage.=A0 And Lord knows I have seen a lot of
> Grummans=20with
> > quite a bit of elevator trim linkage, much more than a new plane would
> have.
> >
>
>OFF-THE-RECORD: I know of one Cheetah that did a split-S at 12,000 feet and
>leveled off at 3,000 feet. At or near 200 indicated for a good portion of
>the way down. Smooth as silk.
>
>
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: Aileron Flexing |
--> TeamGrumman-List message posted by: TeamGrumman@aol.com
In a message dated 4/6/06 4:36:46 PM, 923te@cox.net writes:
> The groove is about .5" Long by .25 wide and is .014 at its deepest point.
> It is about 16" from the tube end.
>
Is this on the end near where it goes into the fuselage? It may have been
caused by the bolt that goes through the flap torque tube. That's pretty
common. You're allowed 0.030 inches deep. There are a few things you can do
to
fix that. The inner-most aileron bearing support has an adjustment on the
screw holes. Make sure they aileron torque tube is as far away as possible.
Then, make sure you have enough shims (washers) under the special bolts on
the flap torque tube collar to keep the head of the bolt protuding more than
about 3 to 5 thousanths.
Gary
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: | Re: Grumman strength |
--> TeamGrumman-List message posted by: TeamGrumman@aol.com
In a message dated 4/6/06 4:02:18 PM, A1ynk@aol.com writes:
> The aileron hits the stop and
> then the torque tube flexes alowing the other aileron to go up and hit that
> stop.
> Bill Hatton
>
Not true. To go past the stop on the left side you are actually stretching
the cables so the right aileron hits its stop and vice versa.
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: Grumman strength |
--> TeamGrumman-List message posted by: TeamGrumman@aol.com
In a message dated 4/6/06 9:49:39 PM, gilalex@earthlink.net writes:
> Don't forget the one that had aileron flutter at Van Nuys....
>
>
Well, it did NOT have aileron flutter. And, it happend a LONG time after
the AD came out.
I looked at that Tiger to do an estimate on repairs. The ailerons had been
installed wrong. The long bolt that goes through for the aileron stop had
been installed outboard of the stop. Thus, (don't you just love that word) the
aileron stop could not act as a stop. The plane had encountered (or so the
pilot said) wind shear from a jet landing on an adjacent runway. As the
story goes, the pilot tried to correct for the roll and the aileron ripped out.
Funny, but the aileron stop was still there and intact. The other aileron
was still on the plane and the aileron counter-weight had made a mark in the
wingtip where it had gone way past the design limit.
Gary
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! --
|