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wild.blue(at)verizon.net
Guest

Posted: Wed Apr 05, 2006 2:39 pm Post subject: glide ratios

Tim, Dennis, Brian et al--



 



Here's one to try (maybe) next time you're out flying, just for fun and 

training:"



 



You are flying along and its time to land. Problem--the throttle linkage

separates itself from the carburetor leaving the throttle stuck wide open.

Otherwise, everything is operating normally. You are near the runway. How to

get down?



 



This actually happened to Bud Granley a couple of years ago while he was

flying the Unlimited racer "Furias" at Reno and lapping at over 400 mph. 

Nice little Hawker Sea Fury with a great big PW 4360 strapped on the front.



 



BTW he landed with no damage and gas in the tank and, no, he didn't just

pull the mixture, speaking of manhole covers. 



 



Jerry Painter



 



Wild Blue Aviation 



425-876-0865 



wild.blue(at)verizon.net 



http://mysite.verizon.net/res0cs5r/index.html

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Wed Apr 05, 2006 3:04 pm Post subject: glide ratios

Jerry Painter wrote:



 	  Quote: 	
		   You are flying along and its time to land. Problem--the throttle linkage

 separates itself from the carburetor leaving the throttle stuck wide open.

 Otherwise, everything is operating normally. You are near the runway. How to

 get down?


	


With no throttle the M14P has four controls that will modify engine 

power output (the Huosai has five):



1. the prop control;

2. the mag switch;

3. the fuel shut-off lever;

4. the primer;

5. (in the case of the Huosai) the mixture control.



The prop control and the mixture control (Huosai) are going to have 

limited authority. They are not going to reduce power to the point where 

you can get a descent if the throttle is wide open but they can reduce 

the power so that any on-off power control will be less of a difference.



Taking a page from the book of the WW-I Neuport and other aircraft that 

were powered by the Gnome rotary, you can control engine power by 

switching the mags on and off. This will work and works instantly. It is 

just a bit abrupt tho'.



Another possibility is to use the fuel shut off as a gross mixture 

control. By positioning it between full on and full off you can 

partially starve the engine of fuel and cut the power output way back. 

It will be very sensitive but should give you complete control of power 

from full on to full off. (Speaking of Lean of Peak operation ...)



Lastly, you can cut off the fuel with the emergency fuel shut off and 

then use the primer to add a little bit of power at a time. It would 

work somewhat like using the mag switch.



So you use these gross controls to get you into the ballpark from which 

you can safely make a power-off descent to the runway. If you find you 

are a little short you can blip in some power to get you to where you 

want to be. The rest is just a power-off landing.



It will certainly be annoying but it shouldn't constitute a real emergency.



-- 

Brian Lloyd                         361 Catterline Way

brian-yak at lloyd dot com          Folsom, CA 95630

+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-Exupery

_________________
Brian Lloyd
brian-yak at lloyd dot com
+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-Exupery

gus.fraser(at)gs.com
Guest

Posted: Thu Apr 06, 2006 4:39 am Post subject: glide ratios

Return to Sopwith Camel days and pump the mag switch. Stay lower than normal

on power. Switch off the mag then climb to pattern hopefully you will be at

the right final speed after your boost climb. At that point a combination of

mag and side slip to make the runway. Does anyone have an idea at what speed

the prop stops turning ?



Gus



--

Valkyre1(at)comcast.net
Guest

Posted: Thu Apr 06, 2006 5:56 am Post subject: glide ratios

Question.... would the max rpm be exceeded? Sounds  like it would if it's stuck wide open and immediate action isn't  taken. 

 What kind of engine damage in the M14P, if any,  could be expected by the on/off approaches with fuel or mags? ( Not that doing  nothing is even an option here.)

  

 - Val

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Thu Apr 06, 2006 6:21 am Post subject: glide ratios

Valkyre1 wrote:

 	  Quote: 	
		   Question.... would the max rpm be exceeded? 


	


The prop governor should prevent that but there is a response time lag 

in the governor that might allow for a momentary engine overspeed. That 

is why I would probably control engine power with the fuel shut-off or 

the primer.



 	  Quote: 	
		   Sounds like it would if it's 

 stuck wide open and immediate action isn't taken. 


	


Well, that is the scenario -- throttle stuck wide open.



 	  Quote: 	
		   What kind of engine damage in the M14P, if any, could be expected by the 

 on/off approaches with fuel or mags? ( Not that doing nothing is even an 

 option here.)


	


This is an emergency procedure to get the airplane back on the ground in 

one piece. We are talking about an engine tear-down and inspection vs. 

possible loss of the aircraft and pilot in the case of an off-airport 

landing. I wouldn't be worrying about the possible effects on the engine 

at that point.



And when was the last time anyone inspected their throttle linkage 

during pre-flight, hmmm?



One of the things I recall on a spam can (Cessna?) is a spring that 

moved the throttle to about 1/2 if the linkage came off.



-- 

Brian Lloyd                         361 Catterline Way

brian-yak at lloyd dot com          Folsom, CA 95630

+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-Exupery

pilling.k(at)btconnect.co
Guest

Posted: Thu Apr 06, 2006 7:09 am Post subject: glide ratios

Not a good idea to use the fuel shut-off in a Yak unless you want to dead 

stick it in. Its a once only use and needs resetting under the cowl. Not 

easy whilst in the air.



Stick to the Mags.



kp

---

viperdoc(at)mindspring.co
Guest

Posted: Thu Apr 06, 2006 7:36 am Post subject: glide ratios

This is new information. I always close the fuel shutoff in the cockpit

when I am pulling the fuel filter screen. Open it back up after the screen

is re-inserted and safety wired. I have not seen a reset mechanism under

the cowl for the shut off. Just the mechanical linkage is all I have seen.

We test it every year at the time of annual.

What am I missing?

Doc

[quote] [Original Message]

 From: Kevin Pilling <pilling.k(at)btconnect.com>

 To: <yak-list(at)matronics.com>

 Date: 4/6/2006 10:16:13 AM

 Subject: Re: glide ratios



 



 Not a good idea to use the fuel shut-off in a Yak unless you want to dead 

 stick it in. Its a once only use and needs resetting under the cowl. Not 

 easy whilst in the air.



 Stick to the Mags.



 kp

 ---

Scooter

Joined: 10 Jan 2006
Posts: 155

Posted: Thu Apr 06, 2006 7:42 am Post subject: Re: glide ratios

Is this true?  You talking about the red fuel shutoff handle in the Yak-52?  Or is this a Yak-50 thing?

 	  pilling.k(at)btconnect.co wrote: 	
		  Not a good idea to use the fuel shut-off in a Yak unless you want to dead 

stick it in. Its a once only use and needs resetting under the cowl. Not 

easy whilst in the air.



Stick to the Mags.



kp

---

pilling.k(at)btconnect.co
Guest

Posted: Thu Apr 06, 2006 7:58 am Post subject: glide ratios

Dunno......I'm going by the Russian Pilot Notes as supplied with my 

a/c.........is it possibly the colloquial translation.....but if so...why 

safety wire it open ?

Until I'm proved wrong, or have an in-flight fire, I'll leave its safety 

wire intact.



kp

---

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Thu Apr 06, 2006 8:43 am Post subject: glide ratios

Kevin Pilling wrote:

 	  Quote: 	
		   

 

 Not a good idea to use the fuel shut-off in a Yak unless you want to

 dead stick it in. Its a once only use and needs resetting under the

 cowl. Not easy whilst in the air.


	


In the CJ6A it is just an on/off valve. Are you sure it is a "once you

turn it off you are screwed" type valve? That just doesn't make any

sense as having someone accidentally pull it guarantees an immediate

emergency landing with no recovery from the error.



 	  Quote: 	
		   Stick to the Mags.


	


I want to find out about the fuel shut-off first.



Brian Lloyd

pilling.k(at)btconnect.co
Guest

Posted: Thu Apr 06, 2006 8:53 am Post subject: glide ratios

I'll dig out the weighty tomb and read again.



kp

---

dsavarese(at)elmore.rr.co
Guest

Posted: Thu Apr 06, 2006 9:42 am Post subject: glide ratios

Kevin,

Why do you say it needs resetting under the cowl?  You should be able to 

move the red fire control handle in either cockpit from on (forward) to off 

(back) and vice versa without having to open the cowling.  If you can shut 

the fuel off from the cockpit but not back on and as you say, you have to 

open the cowling to reset it, something is definitely not rigged properly.

Dennis



---

dsavarese(at)elmore.rr.co
Guest

Posted: Thu Apr 06, 2006 9:42 am Post subject: glide ratios

Nothing Doc.

Dennis



---

dsavarese(at)elmore.rr.co
Guest

Posted: Thu Apr 06, 2006 9:50 am Post subject: glide ratios

I strongly suggest you test it to make sure you CAN shut the fuel off.  I 

had one 52 where it could not be shut down because of two things happening 

simultaneously.  1- A P-lead had come off the right mag and 2 - the fuel 

shut off/fire control handle would not shut the fuel off because the 

adjustment on the over center arm by the coarse fuel screen was improperly 

adjusted.  The only way I was able to shut it down was to stuff a towel into 

the carburetor intake scoop.  I was behind the nose wheel and reached 

forward to stuff the towel in the intake.   I also turned the primer pump to 

the right (or it could have been left - but that doesn't matter) to force 

the engine to suck more air and lean itself out.   It finally choked itself 

off.



Try shutting the engine down at idle by pulling the fire control/fuel shut 

off.  If it doesn't shut down, you need to adjust the over center arm and 

control rod.

Dennis



---

viperdoc(at)mindspring.co
Guest

Posted: Thu Apr 06, 2006 10:18 am Post subject: glide ratios

Scooter,

Its a YAK 52 issue that I have never seen. We do not safety wire our fuel

shut off valves. There surely is a Russian pilot running around with a call

sign like Handles, IQ ('quisitive Queer), Cg (Curious George), or Switches.

That would be the one that pulled the leaver to see what it would do!!

That would probably be the reason for someone safety wiring the fuel shut

off lever. 

But that was just a thought on my part! 

Have you ever tried priming your YAK with the fuel shutoff lever closed?

That will get your attention also.

Doc

 	  Quote: 	
		   [Original Message]

 From: Scooter <yakk52(at)verizon.net>

 To: <yak-list(at)matronics.com>

 Date: 4/6/2006 10:52:57 AM

 Subject: Re: glide ratios

 Is this true?  You talking about the red fuel shutoff handle in the

Yak-52?  Or is this a Yak-50 thing?

 	  Quote: 	

 pilling.k(at)btconnect.co wrote:

 > Not a good idea to use the fuel shut-off in a Yak unless you want to

dead 

 	  Quote: 	
		   > stick it in. Its a once only use and needs resetting under the cowl.

Not 

 	  Quote: 	
		   > easy whilst in the air.

 > 

 > Stick to the Mags.

 > 

 > kp

 > ---

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=26744#26744

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Thu Apr 06, 2006 11:34 am Post subject: glide ratios

Kevin Pilling wrote:

 	  Quote: 	
		   

 

 Dunno......I'm going by the Russian Pilot Notes as supplied with my

 a/c.........is it possibly the colloquial translation.....but if

 so...why safety wire it open ?


	


My answer to this would be, "To keep someone from trying to take off

with the fuel turned off." OTOH, I doubt there would be enough fuel in

the strainer to get the airplane on the runway and airborne even if you

turned it off just as you turned onto the runway for take-off.



Perhaps a better reason would be to prevent someone from turning off the

fuel when they are trying to activate the alternate air (at least in the

CJ6A that is a more likely scenario).



 	  Quote: 	
		   Until I'm proved wrong, or have an in-flight fire, I'll leave its safety

 wire intact.


	


It isn't that hard to check on the ground. Cut the safety wire, turn the

emergency shut-off to the off position, turn it back on, and verify fuel

flow. If the fuel is back on, redo the safety wire. If the fuel is off

and must be reset under the cowl (which I doubt), reset it, redo the

safety wire, and then tell the Yak-50 users here that their aircraft is

different from the Yak-52 and CJ6A. Cost? about 1 minute of time and a

piece of safety wire.



It is probably not a good idea to make assumptions about aircraft

systems. It is much better to know for sure by testing them. As you say,

even errors in translation could be a problem.



This is a really interesting point about documentation. A fair amount of

what has been written is in error (including newspapers, text books, and

operating manuals). The only way to know for sure that something is the

way we think it is, is to try it and see. Sure, take care to make sure

that testing will not involve any risk to aircraft or pilot but make

sure you understand how it works.



Brian Lloyd

brian HYPHEN yak AT lloyd DOT com

dsavarese(at)elmore.rr.co
Guest

Posted: Thu Apr 06, 2006 11:51 am Post subject: glide ratios

Brian,

On the 52 the emergency air is on the opposite side of the cockpit.  Not 

chance of messing up there.



A great way to check and see if the fire control/fuel shutoff is functioning 

properly without running the engine is to pull the fire control/fuel shut 

off back, then turn the primer pump to the left (system side) and attempt to 

pressurize the fuel system.  After a few strokes, if the fuel shut off is 

properly adjusted, it will be virtually impossible to push the primer pump 

in.  Now move the fuel shut off forward and pump the primer pump at the same 

time you are doing this.  The primer pump should now pump normally 

immediately.  If after pulling the fuel shut off closed and you begin to 

pump the primer to the system side and it never feels any different than 

usual, your fuel shut off arm and cable are improperly adjusted.

Dennis



---

viperdoc(at)mindspring.co
Guest

Posted: Thu Apr 06, 2006 2:02 pm Post subject: glide ratios

Same with the 50. It is just on opposite sides of the instrument panel. ER

AIR on right and Fuel Shut Off on the left.

Doc

 	  Quote: 	
		   [Original Message]

 From: A. Dennis Savarese <dsavarese(at)elmore.rr.com>

 To: <yak-list(at)matronics.com>

 Date: 4/6/2006 2:57:40 PM

 Subject: Re: glide ratios



 

<dsavarese(at)elmore.rr.com>
	


 	  Quote: 	
		  

 Brian,

 On the 52 the emergency air is on the opposite side of the cockpit.  Not 

 chance of messing up there.



 A great way to check and see if the fire control/fuel shutoff is

functioning 
	


 	  Quote: 	
		   properly without running the engine is to pull the fire control/fuel shut 

 off back, then turn the primer pump to the left (system side) and attempt

to 
	


 	  Quote: 	
		   pressurize the fuel system.  After a few strokes, if the fuel shut off is 

 properly adjusted, it will be virtually impossible to push the primer

pump 
	


 	  Quote: 	
		   in.  Now move the fuel shut off forward and pump the primer pump at the

same 
	


[quote] time you are doing this.  The primer pump should now pump normally 

 immediately.  If after pulling the fuel shut off closed and you begin to 

 pump the primer to the system side and it never feels any different than 

 usual, your fuel shut off arm and cable are improperly adjusted.

 Dennis



 ---

netmaster15(at)juno.com
Guest

Posted: Thu Apr 06, 2006 3:39 pm Post subject: glide ratios

VAL, 

  In ref to the M-14P

 If the throttle is stuck wide open, with prop in full low pitch and the  mags are turned to the  "ÓFF" position for even a brief time--if the mag  switches are turned back to "BOTH", I guarantee the instant acceleration and  torque will get your attention when that engine comes back to life. With the  instant application of torsional forces on the engine mount an even bigger shock  may await you if the engine package leaves the airframe. Think you can modulate  the power by tweaking the mag switch? Maybe not! Look at Dennis' report of a  DUALl failure involving the loss of the "P " lead concurrently with the  malfunction of the fuel shutoff actuator. The problem presented here   points out that it is damned difficult to shut one of these Bangers down when  engine controls decide they wont work anymore.

      True, the M14P is not a P/W 3350 or an R 2800 but  the engine mount in our YAKs is a limit design calibrated proportionately   to the forces produced  by the normal operation  of our now 25  year old  airframes, which, in many cases,  have been exposed to some  extreme maneuvers as well as changes in the molecular structure of the metal  during the aging process.  My YAK 50 was flown by Victor Smolens in the  World  Aerobatic Championship held in Sydney, Australia. Victor was a great  pilot but his first concern was not for the structure of the airplane. That's  the reason the Russians replaced the wings periodically on these YAK 50s   Metal fatigue is insideous and often takes place out of sight so, who knows how  much life is left in these engine mounts? And how much torsional stress can they  stand?  Tweak the mags on final?  If you're slow enough and low  enough, that would be an inconvenient time to  explore the parameters of  the torque roll when that engine comes back to life. Yet, we work with what  we have and hope to use the airplane again after this next landing.

  

       CLIFF

  

 On Thu, 6 Apr 2006 07:55:01 -0600 "Valkyre1" <Valkyre1(at)comcast.net (Valkyre1(at)comcast.net)> writes:

  	  Quote: 	
		     Question.... would the max rpm be exceeded?    Sounds like it would if it's stuck wide open and immediate action isn't    taken. 

   What kind of engine damage in the M14P, if any,    could be expected by the on/off approaches with fuel or mags? ( Not that doing    nothing is even an option here.)

    

   - Val

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Thu Apr 06, 2006 7:18 pm Post subject: glide ratios

Cliff Umscheid wrote:



 	  Quote: 	
		   torsional stress can they stand?  Tweak the mags on final?  If you're 

 slow enough and low enough, that would be an inconvenient time to 

  explore the parameters of the torque roll when that engine comes back 

 to life. Yet, we work with what we have and hope to use the airplane 

 again after this next landing.


	


So you experiment with the mags when you have a little altitude so you 

know how the airplane is going to respond when you turn the mags on and off.



I guess I tend to be the devil's advocate here. The engine produces only 

so much torque. When you switch the mags on that torque is there but it 

is the same torque that the engine mount is under any other time you are 

at full-throttle and high RPM. I don't think the mount is going to give way.



OTOH, if you turn the mag switch on and off rapidly you might be able to 

set up a resonance that could cause a problem with the airframe or 

engine mount.



So you pull the prop control all the way back. That isn't going to 

change the torque much but it is going to reduce the power output of the 

engine. This will make the power changes when you turn the mags on and 

off less abrupt and will make the glide a bit better as the prop in 

coarse-pitch/low-RPM is going to produce less drag when the engine is 

not producing power and less power when the engine IS producing power. 

Now your mag cuts will have less of an effect.



I still think you can modulate the power output with the fuel cut-off 

lever if you are careful.



-- 

Brian Lloyd                         361 Catterline Way

brian-yak at lloyd dot com          Folsom, CA 95630

+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-Exupery

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