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B25Flyer

Joined: 06 Mar 2006
Posts: 11

Posted: Mon Mar 06, 2006 6:41 am Post subject: Re: Minimum altitude to return to airport

I am baaaack!!!!!!!



Kevin Horton told me this subject had raised it's head again.   



There is NO DOUBT that the turnback after takeoff can be completed in an RV.   There is also NO DOUBT that each year several people get killed trying to do it.  This happens in all kinds of airplanes including RV's.



I am alive today because I overcame the incredible urge to turnback.  I wrote this years ago when this topic came up.  Please read the story at 



http://www.petroblend.com/dougr/dnt-turn.htm



As the Defender of "Don't Turn Back"  I remain!



Doug Rozendaal

pitts_pilot(at)bellsouth.
Guest

Posted: Mon Mar 06, 2006 7:30 am Post subject: Minimum altitude to return to airport

If you haven't read Doug's piece, then do it now.  It's interesting 

reading, and I couldn't agree more.  Although both of my off-field 

emergency landings occurred far from an airport, I went through much the 

same steps that Doug did.  But I handled my two  emergencies 

differently.  When the prop on my Pitts departed in flight (the prop 

flange failed due to fatigue), I spent valuable time trying to figure 

out what happened, and actually tried twice to use whatever portions of 

the prop were still there (the denial part!).  I was in the 2200' to 

2500' range when it happened.   After I became an unlicensed glider 

pilot, the safe landing on a road was uneventful, thank you very much.



The second incident was in my Traumahawk.  At 1200', flying in a 

corridor through some class B space, the engine started to run rough, 

and finally lost enough power so we couldn't stay in the air.  Over 

older neighborhoods with lakes and huge oak trees, I assessed my landing 

options rather quickly while doing my emergency cockpit procedures. 

 There was a large highway, but if I landed short, it would have been 

nasty, so I discarded it immediately.  Off my left wing I saw a white 

oblong something amidst the green trees/houses.  I picked it, and didn't 

waver from my choice.  I had to slip the Traumahawk a lot to lose 

altitude and airspeed, and plopped the bird down ..... in the 

percolation pond for the Winter Springs (FL) Reclaimed Water System. 

 they had built a 6' berm around ground level and put sugar sand in the 

bottom.  This was fortuitous as the Traumahawk was stopped is less than 

300'.  My best short field landing to date.  The cause of this one was 

the missing cotter pin in the arm that holds the carb float.  The pin 

backed out far enough for the float to cock, become jammed and allow the 

free-flowing fuel to flood the engine in flight.  The carb had been 

rebuilt by an A&P prior to my purchase 6 months or so before.



In both instances, the airplanes were disassembled and made their way 

home on a trailer to fly again.



If you've read this far, I have some personal observations.  



You never know how you're going to handle the emergency until it becomes 

real.



Every inflight emergency is unique and unlike anyone elses emergency. 

 You can learn from others thought processes, but your situation will 

always be different is some or many ways.



Some people have been killed trying to save the airplane.  That's the 

only reason to compel someone to turn back to the airport.  My airplanes 

are expendable.  I have had so much pleasure from all of them that they 

don't owe me anything.  That doesn't prevent me from trying to save both 

of our butts!!!



I like the skin, tin, ticket quote.  It ranks up there with 'fly the 

airplane as deep into the crash as you can'.  Priceless.

Thanks, Doug, for weighing in again.  I missed you!

Linn

do not archive

B25Flyer wrote:



 	  Quote: 	
		  



I am baaaack!!!!!!!



Kevin Horton told me this subject had raised it's head again.   



There is NO DOUBT that the turnback after takeoff can be completed in an RV.   There is also NO DOUBT that each year several people get killed trying to do it.  This happens in all kinds of airplanes including RV's.



I am alive today because I overcame the incredible urge to turnback.  I wrote this years ago when this topic came up.  Please read the story at 



http://www.petroblend.com/dougr/dnt-turn.htm



As the Defender of "Don't Turn Back"  I remain!



Doug Rozendaal





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=19895#19895

pitts_pilot(at)bellsouth.
Guest

Posted: Mon Mar 06, 2006 7:30 am Post subject: Minimum altitude to return to airport

If you haven't read Doug's piece, then do it now.  It's interesting 

reading, and I couldn't agree more.  Although both of my off-field 

emergency landings occurred far from an airport, I went through much the 

same steps that Doug did.  But I handled my two  emergencies 

differently.  When the prop on my Pitts departed in flight (the prop 

flange failed due to fatigue), I spent valuable time trying to figure 

out what happened, and actually tried twice to use whatever portions of 

the prop were still there (the denial part!).  I was in the 2200' to 

2500' range when it happened.   After I became an unlicensed glider 

pilot, the safe landing on a road was uneventful, thank you very much.



The second incident was in my Traumahawk.  At 1200', flying in a 

corridor through some class B space, the engine started to run rough, 

and finally lost enough power so we couldn't stay in the air.  Over 

older neighborhoods with lakes and huge oak trees, I assessed my landing 

options rather quickly while doing my emergency cockpit procedures. 

 There was a large highway, but if I landed short, it would have been 

nasty, so I discarded it immediately.  Off my left wing I saw a white 

oblong something amidst the green trees/houses.  I picked it, and didn't 

waver from my choice.  I had to slip the Traumahawk a lot to lose 

altitude and airspeed, and plopped the bird down ..... in the 

percolation pond for the Winter Springs (FL) Reclaimed Water System. 

 they had built a 6' berm around ground level and put sugar sand in the 

bottom.  This was fortuitous as the Traumahawk was stopped is less than 

300'.  My best short field landing to date.  The cause of this one was 

the missing cotter pin in the arm that holds the carb float.  The pin 

backed out far enough for the float to cock, become jammed and allow the 

free-flowing fuel to flood the engine in flight.  The carb had been 

rebuilt by an A&P prior to my purchase 6 months or so before.



In both instances, the airplanes were disassembled and made their way 

home on a trailer to fly again.



If you've read this far, I have some personal observations.  



You never know how you're going to handle the emergency until it becomes 

real.



Every inflight emergency is unique and unlike anyone elses emergency. 

 You can learn from others thought processes, but your situation will 

always be different is some or many ways.



Some people have been killed trying to save the airplane.  That's the 

only reason to compel someone to turn back to the airport.  My airplanes 

are expendable.  I have had so much pleasure from all of them that they 

don't owe me anything.  That doesn't prevent me from trying to save both 

of our butts!!!



I like the skin, tin, ticket quote.  It ranks up there with 'fly the 

airplane as deep into the crash as you can'.  Priceless.

Thanks, Doug, for weighing in again.  I missed you!

Linn

B25Flyer wrote:



 	  Quote: 	
		  



I am baaaack!!!!!!!



Kevin Horton told me this subject had raised it's head again.   



There is NO DOUBT that the turnback after takeoff can be completed in an RV.   There is also NO DOUBT that each year several people get killed trying to do it.  This happens in all kinds of airplanes including RV's.



I am alive today because I overcame the incredible urge to turnback.  I wrote this years ago when this topic came up.  Please read the story at 



http://www.petroblend.com/dougr/dnt-turn.htm



As the Defender of "Don't Turn Back"  I remain!



Doug Rozendaal





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=19895#19895

Neal.George(at)maxwell.af
Guest

Posted: Mon Mar 06, 2006 8:32 am Post subject: Minimum altitude to return to airport

>I am baaaack!!!!!!! <



Best news I've had in weeks.  

Welcome back Doug!



Neal

RV-7 N8ZG (wiring)

gmcjetpilot(at)yahoo.com
Guest

Posted: Mon Mar 06, 2006 11:26 am Post subject: Minimum altitude to return to airport

>From: luckymacy(at)comcast.net (lucky)

 	  Quote: 	
		  Subject: Re: Minimum altitude to return to airport



The point wasn't to read more emails from folks who have never 

done this practice in an RV and just rehashed their previous 

soapboxes.  It was to update the list with a real tried RV 

  >datapoint. It doesn't mean it will work for each pilot/plane combo 
	


  >every time but it does demonstrate that it CAN be done and 

  >BETTER yet it actually showed a bank amount and min 

  >airspeed amount and altitude loss amount.  Real RV data beats 

  >soapbox.

      

  

Lucky:

  

First as far as soapbox and folks who have never done this in a 

RV, you might like to know that several of the folks on this list 

are literally test pilots and long time RV pilot and instructors. 

Although I never have done a 400agl turn back in a RV, I am a 

10,000 hr ATP, over a 1000 in RV's and 2000 hrs dual given as 

a CFI (inst/me). 

   

  I do think it is important to point out that 400 agl COULD be 

dangerous in (our) opinion, I understand your point. It is a data 

point and is possible if you do XYZ. I got that, as well as those 

who responded, but not everyone my get it, and I think it is 

important that the emphasis be made. I know you might feel a 

little ganged up on, I understand, but that is not the intent or  

to take away from Jan's interesting DEMO. 

  

It's a good thing to emphasise the danger for the average pilot 

caught unaware, that making low altitude 60 degree BANK 

turns are sporty. Quick what is your new stall speed at 60 

degrees? Have you practiced an accelerate stall/recovery? 

Steep turns at altitude? Power off glide to landing? I would 

  go for these at altitude first.

   

   

  The average pilot is not prepared mentally or skill wise for 

  radical max performance maeuvers at any altitude (good, bad, 

  ugly it is true). We all get rusty. I fly a jet on autopilot. If I don't 

  kick it off and hand fly my stick and rudder suffer. So one good 

  thing out of this topic is practice and stay current, but you can 

  do it higher up in case you are human and make a mistake, you 

  have room to recover. For those with super human skill and can 

  do a power off go around (joke), you know who you are.

   

   

  Every ones caution is valid. I don't agree with ALWAYS go 

straight either. You say we all know. Not every pilot might know 

  why a 400 agl, 270 degree turn (225 left, 45 right to line up) 

is hazards. Jan may be able to do it knowing the engine is there 

  but add a little distraction, oil on the windscreen, vibration he 

  might not be so smooth. Not everyone is named LUCKY! either 

   

   

  As a CFI, I and most CFI's teach what will work. One thing for 

sure,  controlled flight, wings level, at min speed is WAY more 

survivable than a stall spin into the ground. Not every one has the 

SKILL and practice as Jan does in this maneuver. As you and 

everyone pointed out that every takeoff, airport, flight and aircraft 

condition is differnt. Mental preparedness and practice of  basic 

skills (slow flight, stalls, accelerate stall, steep turns, pwr-off glide 

to a landing) is critical. Most practice can be done at altitude. I 

can't see practicing higher G banks near stall, near the ground is 

really prudent. You can do this at 3000 agl. 

  

One commercial maneuver is a steep descending spiral over a 

  point to a power off landing. I found that really confidence building 

  and increased my ability to divide attention from out/in side and 

  maintain while maintaining a higher G turn. 

  

I agree with everything you said except the soapbox. I think 

everyone has valid points, even if they never did a 400 agl turn 

back in a RV. With that said, the day my engine quits on the 

cross-wind at 500 agl and I see the runway is available, I may  

make a decision to go for the runway. I will base that more on my 

power off glide practice and steep turns and accelerate stall 

recovery (awareness / avoidance) practice. A Demo by a skilled 

pilot like Jan is an eye opener, but most RV pilots are not able to 

do this maneuver as safely in a real stressful situation. Not that it 

is a good thing, it is realistic. Be real, real safe and conservative. 

   

  FACTS:

Controlled flight (at min speed) into the ground = survivable

Uncontrolled flight (stall spin) into the ground = not survivable 

  Stall Spd:  60 deg bank=1.4 x stall; 76 deg bank = 2 x stall

   

    "Ye will bust thy ass when ground cometh up and smite 

  thee mightily."



   

  Be safe, and go practice all your private (student) pilot 

  maneuvers at altitude today. If commercial rated practice 

  those maneuvers as well.  

  

George

		

---------------------------------

Bring photos to life! New PhotoMail  makes sharing a breeze.

cgreimer(at)mts.net
Guest

Posted: Mon Mar 06, 2006 5:14 pm Post subject: Minimum altitude to return to airport

I think we should also bring the subject of airspeed into this discussion. 

As in, how fast are you going when the engine quits. Doing 120 knots at 500 

feet a given distance from the runway threshold might give you enough energy 

to make that 180 degree turn back to the runway, while doing 80 knots in the 

same situation might not. This will depend on what speed you established on 

the climb and your overall rate of climb (better for constant-speed prop of 

course). It is total energy available to you that matters in a turn-back 

maneuver, and that consists of kinetic (airspeed) plus potential (altitude) 

energy. This is pretty clear in a fixed pitch RV-6 when you carry an extra 

10 knots into the late downwind (doh!) and have to extend it a half mile or 

use some other energy sapping maneuver, like dropping the flaps early.



Airspeed aside, the guy with the constant speed prop climbing at Vx is quite 

likely to still be OVER the runway when the 500' engine failure occurs, 

while the fixed pitch guy climbing at Vy is a half mile away from the 

airport at the same altitude.



Curt

RV-6 C-GCAR

375 hours



---

hawk(at)digisys.net
Guest

Posted: Mon Mar 06, 2006 7:07 pm Post subject: Minimum altitude to return to airport

George ( gmcjetpilot(at)yahoo.com ) asked,

    "Quick what is your new stall speed at 60 degrees?"

*************

Since the stall speed is not related to bank angle in any way, the answer 

is,

"just about anything you want it to be."  You establish your stall speed by 

setting your load factor.



Performing the turnback maneuver using 60 degrees of bank and +1.5 Gz will 

result in a good rate of turn with a generally acceptable loss of altitude. 

Even using +1.25 Gz will yield a pretty good result, although significantly 

more altitude is lost in the turn, as compared to loading the aircraft up 

closer to max available Gz  at the chosen glide speed (If we use 100 KIAS as 

our best glide speed, over +3.5 Gz is available).  At the lower Gz levels, 

IAS will also tend to increase at a higher rate during the turn, the 

magnitude of the increase largely depending on the  pitch angle at the entry 

to the turn.



Achieving good turn performance without giving away all the stall margin is 

certainly possible.



Hawkeye Hughes

gmcjetpilot(at)yahoo.com
Guest

Posted: Tue Mar 07, 2006 3:05 am Post subject: Minimum altitude to return to airport

 	  Quote: 	
		  From: "REHughes" <hawk(at)digisys.net>

Subject: Re: Minimum altitude to return to airport

REHughes" <hawk(at)digisys.net> also wrote:

  >Since the stall speed is not related to bank angle in any way

  I had to reply.

  Hawkeye: You could not be anymore wrong, and I will tell you 

  why. If you want to be correct you should say AOA is most 

  relevant to stall, ie critical angle of attack.

  I was referring to a sustained 60 degree banked TURN. My point 

  is for anyone thinking of a low altitude, high bank angle turn, what 

  is your stall speed, ie, what speed are you going to maintain. If 

  you can't think of right now at your easy chair you will not know 

  it when the engine quits. That was the point of the question? I 

  guess I could have said what is your load factor? or AOA? 

  However to address you assertion that bank angle and stall speed 

  are not related, since they are, I will explain.

  Below link is everything you want to know about Bank angle and Gs 

  and applies to RV's or the Space Shuttle, I worked as an engineer  

  before flying for the airlines, so let the equations below speak:

  http://www.aerospaceweb.org/question/performance/q0146.shtml

  (notice, stall speed and bank angle can be expressed. Also notice 

  the generic concept, min flying speed goes UP with bank. That's the 

  point. Notice over 60 bank stall speed goes up quickly. 

  Yes we all know that AOA is critical, but there is a bank angle 

  (airspeed) relationship. Obviously AOA is related to load factor, 

  however you don't fly staring at a G-meter (except may be during 

  aerobatics). 

  We fly indicated airspeed (IAS). Obviously an AOA instrument is 

  most relevant to stall (at any load factor) since you can be wings 

  level and pull all the Gs you want or attitude. 

  Unless you have an AOA, you fly a higher indicated airspeed for 

  a given bank angle to get an **approx**  stall margin, typically 

  1.3 x stall. 

  You say bank angle is not related to load factor? I think you are 

  arguing a moot point relative to making a turn back to the 

  airport.

  The rest of your point (below) about efficient turns and having Gz 

  available and **giving away stall speed**, makes no sense. I guess 

  you mean giving away stall margin? 

  Also when *pulling Gs" you will increase drag and loose airspeed 

  and/or increase rate of descent unless thrust is increased. Is this 

  what U want close to ground? (increased descent rate, low IAS)

  Regardless it kind of muddies the waters from the main Q:

  What are you going to do when the engine quits at the worst time? 

  Fly the plane, fly the plane and maintain control to the ground, 

  whether on the airport or off field. 

  Again stall margin and bank angle in a sustained turn ARE relative.

  Discussion of "efficient" turns are not relevant. What is critical is 

  being in a steep bank, high descent rate near the ground.

  Cheers George

  >"REHughes" <hawk(at)digisys.net> also wrote:

 	  Quote: 	

  >Since the stall speed is not related to bank angle in any way, the 

 	  Quote: 	
		  answer is, "just about anything you want it to be."  You establish 

  >your stall speed by setting your load factor.

 	  Quote: 	

Performing the turnback maneuver using 60 degrees of bank and 

  >+1.5 Gz will result in a good rate of turn with a generally acceptable 

  >loss of altitude. Even using +1.25 Gz will yield a pretty good result, 

  >although significantly more altitude is lost in the turn, as compared 

  >to loading the aircraft up closer to max available Gz  at the chosen 

  >glide speed (If we use 100 KIAS as our best glide speed, over 

  >+3.5 Gz is available).  At the lower Gz levels, IAS will also tend to 

  >increase at a higher rate during the turn, the magnitude of the 

  >increase largely depending on the pitch angle at the entry to the 

  >turn.

 	  Quote: 	

Achieving good turn performance without giving away all the stall 

margin is certainly possible.

Hawkeye Hughes

---------------------------------

Bring photos to life! New PhotoMail  makes sharing a breeze.

luckymacy(at)comcast.net
Guest

Posted: Tue Mar 07, 2006 3:31 am Post subject: Minimum altitude to return to airport

Again, the pre flight briefed and demo'd numbers:

120 mph climbout with fixed pitch prop, flaps up and at

400 feet AGL pulled power back to idle

rolled into 60 degree bank and not one degree more and 

pulled elevator firmly but did not let the airspeed get down to his PRE ESTABLISHED ABSOLUTE MIN AND BRIEFED BEFORE FLIGHT 80 mph.

The RV had no trouble doing this.

We leveled off with ~100 foot altitude loss and probably more than 90 mph airspeed but the nose was kept low after level off to pick up best glide speed which allowed a lot off energy to pull to flare with. The runway displacement was maybe a couple of hundred of feet.  We turned into the wind to to keep it that way.  No obsticles to contend with on the way down on either side.

Lucky

-------------- Original message -------------- 

From: <gmcjetpilot(at)yahoo.com> 

 	  Quote: 	

 >From: "REHughes" 

 >Subject: Re: Minimum altitude to return to airport 

 > 

 >REHughes" also wrote: 

 > 

 >Since the stall speed is not related to bank angle in any way 

 I had to reply. 

 Hawkeye: You could not be anymore wrong, and I will tell you 

 why. If you want to be correct you should say AOA is most 

 relevant to stall, ie critical angle of attack. 

 I was referring to a sustained 60 degree banked TURN. My point 

 is for anyone thinking of a low altitude, high bank angle turn, what 

 is your stall speed, ie, what speed are you going to maintain. If 

 you can't think of right now at your easy chair you will not know 

 it when the engine quits. That was the point of the question? I 

 guess I could have said what is your load factor? or AOA? 

 However to address you assertion that bank angle and stall speed 

 are not related, since they are, I will explain. 

 Below link is everything you want to know about Bank angle and Gs 

 and applies to RV's or the Space Shuttle, I worked as an engineer 

 before flying for the airlines, so let the equations below speak: 

 http://www.aerospaceweb.org/question/performance/q0146.shtml 

 (notice, stall speed and bank angle can be expressed. Also notice 

 the generic concept, min flying speed goes UP with bank. That's the 

 point. Notice over 60 bank stall speed goes up quickly. 

 Yes we all know that AOA is critical, but there is a bank angle 

 (airspeed) relationship. Obviously AOA is related to load factor, 

 however you don't fly staring at a G-meter (except may be during 

 aerobatics). 

 We fly indicated airspeed (IAS). Obviously an AOA instrument is 

 most relevant to stall (at any load factor) since you can be wings 

 level and pull all the Gs you want or attitude. 

 Unless you have an AOA, you fly a higher indicated airspeed for 

 a given bank angle to get an **approx** stall margin, typically 

 1.3 x stall. 

 You say bank angle is not related to load factor? I think you are 

 arguing a moot point relative to making a turn back to the 

 airport. 

 The rest of your point (below) about efficient turns and having Gz 

 available and **giving away stall speed**, makes no sense. I guess 

 you mean giving away stall margin? 

 Also when *pulling Gs" you will increase drag and loose airspeed 

 and/or increase rate of descent unless thrust is increased. Is this 

 what U want close to ground? (increased descent rate, low IAS) 

 Regardless it kind of muddies the waters from the main Q: 

 What are you going to do when the engine quits at the worst time? 

 Fly the plane, fly the plane and maintain control to the ground, 

 whether on the airport or off field. 

 Again stall margin and bank angle in a sustained turn ARE relative. 

 Discussion of "efficient" turns are not relevant. What is critical is 

 being in a steep bank, high descent rate near the ground. 

 Cheers George 

 >"REHughes" also wrote: 

 > 

 >Since the stall speed is not related to bank angle in any way, the 

 >answer is, "just about anything you want it to be." You establish 

 >your stall speed by setting your load factor. 

 > 

 >Performing the turnback maneuver using 60 degrees of bank and 

 >+1.5 Gz will result in a good rate of turn with a generally acceptable 

 >loss of altitude. Even using +1.25 Gz will yield a pretty good result, 

 >although significantly more altitude is lost in the turn, as compared 

 >to loading the aircraft up closer to max available Gz at the chosen 

 >glide speed (If we use 100 KIAS as our best glide speed, over 

 >+3.5 Gz is available). At the lower Gz levels, IAS will also tend to 

 >increase at a higher rate during the turn, the magnitude of the 

 >increase largely depending on the pitch angle at the entry to the 

 >turn. 

 > 

 >Achieving good turn performance without giving away all the stall 

 >margin is certainly possible. 

 > 

 >Hawkeye Hughes 

 --------------------------------- 

 Bring photos to life! New PhotoMail makes sharing a breeze. 

Again, the pre flight briefed anddemo'd numbers:

120 mph climbout with fixed pitch prop, flaps up and at

400 feet AGL pulled power back to idle

rolled into 60 degree bank and not one degree more and 

pulled elevator firmly but did not let the airspeed get down to his PRE ESTABLISHED ABSOLUTE MIN AND BRIEFED BEFORE FLIGHT 80 mph.

The RV had no trouble doing this.

We leveled off with ~100 foot altitude loss and probably more than 90 mph airspeed but the nose was kept low after level off to pick up best glide speed which allowed a lot off energy topull to flare with.The runway displacement was maybe a couple of hundred of feet. We turned into the wind to to keep it that way. No obsticles to contend with on the way down on either side.

Lucky

-------------- Original message -------------- 

From: gmcjetpilot(at)yahoo.com 

 -- RV-List message posted by: <GMCJETPILOT(at)YAHOO.COM>

 From: "REHughes" <HAWK(at)DIGISYS.NET>

 Subject: Re: Minimum altitude to return to airport 

 REHughes" <HAWK(at)DIGISYS.NET>also wrote: 

 Since the stall speed is not related to bank angle in any way 

 I had to reply. 

 Hawkeye: You could not be anymore wrong, and I will tell you 

 why. If you want to be correct you should say AOA is most 

 relevant to stall, ie critical angle of attack. 

 I was referring to a sustained 60 degree banked TURN. My point 

 is for anyone thinking of a low altitude, high bank angle turn, what 

 is your stall speed, ie, what speed 

 are you going to maintain. If 

 you can't think of right now at your easy chair you will not know 

 it when the engine quits. That was the point of the question? I 

 guess I could have said what is your load factor? or AOA? 

 However to address you assertion that bank angle and stall speed 

 are not related, since they are, I will explain. 

 Below link is everything you want to know about Bank angle and Gs 

 and applies to RV's or the Space Shuttle, I worked as an engineer 

 before flying for the airlines, so let the equations below speak: 

 http://www.aerospaceweb.org/question/performance/q0146.shtml 

 (notice, stall speed and bank angle can be expressed. Also notice 

 the generic concept, min flying speed goes UP with bank. That's the 

 point. Notice over 60 bank stall speed goes up quickly. 

 Yes we all

  know that AOA is critical, but there is a bank angle 

 (airspeed) relationship. Obviously AOA is related to load factor, 

 however you don't fly staring at a G-meter (except may be during 

 aerobatics). 

 We fly indicated airspeed (IAS). Obviously an AOA instrument is 

 most relevant to stall (at any load factor) since you can be wings 

 level and pull all the Gs you want or attitude. 

 Unless you have an AOA, you fly a higher indicated airspeed for 

 a given bank angle to get an **approx** stall margin, typically 

 1.3 x stall. 

 You say bank angle is not related to load factor? I think you are 

 arguing a moot point relative to making a turn back to the 

 airport. 

 The rest of your point (below) about efficient turns and having Gz 

 available and **giving away stall speed**, makes no sense. I guess 

 you m

 ean giving away stall margin? 

 Also when *pulling Gs" you will increase drag and loose airspeed 

 and/or increase rate of descent unless thrust is increased. Is this 

 what U want close to ground? (increased descent rate, low IAS) 

 Regardless it kind of muddies the waters from the main Q: 

 What are you going to do when the engine quits at the worst time? 

 Fly the plane, fly the plane and maintain control to the ground, 

 whether on the airport or off field. 

 Again stall margin and bank angle in a sustained turn ARE relative. 

 Discussion of "efficient" turns are not relevant. What is critical is 

 being in a steep bank, high descent rate near the ground. 

 Cheers George 

 "REHughes" <HAWK(at)DIGISYS.NET>also wrote: 

 Since the stall speed is not related to bank angle in any way, the

 answer is, "just about anything you want it to be." You establish 

 your stall speed by setting your load factor. 

 Performing the turnback maneuver using 60 degrees of bank and 

 +1.5 Gz will result in a good rate of turn with a generally acceptable 

 loss of altitude. Even using +1.25 Gz will yield a pretty good result, 

 although significantly more altitude is lost in the turn, as compared 

 to loading the aircraft up closer to max available Gz at the chosen 

 glide speed (If we use 100 KIAS as our best glide speed, over 

 +3.5 Gz is available). At the lower Gz levels, IAS will also tend to 

 increase at a higher rate during the turn, the magnitude of the 

 increase largely depending on the pitch angle at the entry to the 

 turn. 

 Achieving good turn performance without giving away all the stall 

  margin is certainly possible. 

 Hawkeye Hughes 

 --------------------------------- 

 Bring photos to life! New PhotoMail makes sharing a breeze. 

 ======================================

JVanLaak(at)aol.com
Guest

Posted: Tue Mar 07, 2006 4:23 am Post subject: Minimum altitude to return to airport

My friend Hawkeye (former flight surgeon and naval aviator) was  referring to 

the point that you can be in 90 degrees of bank with one G on the  airframe 

and the stall speed is what it would be if level.  Likewise, you  could be in a 

4 G pull wings level and the stall would be twice the 1 G  value.

 

So in application, if you use a 90 degree bank but only 1 G the airplane  

with large stall margin will turn rapidly but the nose will fall.  If you  have 

the vertical room to permit that it might be a good trade.

 

Jim

 

RV-6 N79RL.

rv7(at)b4.ca
Guest

Posted: Tue Mar 07, 2006 8:29 am Post subject: Minimum altitude to return to airport

On 3:29:57 2006-03-07 luckymacy(at)comcast.net (lucky) wrote:

 	  Quote: 	
		   



 Again, the pre flight briefed and demo'd numbers:



 120 mph climbout with fixed pitch prop, flaps up and at

 400 feet AGL pulled power back to idle

 rolled into 60 degree bank and not one degree more and

 pulled elevator firmly but did not let the airspeed get down to his

 PRE ESTABLISHED ABSOLUTE MIN AND BRIEFED BEFORE FLIGHT 80 mph.



 The RV had no trouble doing this.


	


And again, as others have pointed out, this was a contrived situation.  The

pilot briefed and prepared for an engine out on takeoff, and everything

went according to plan.



Try the same thing on a climbout when you're not expecting an engine

failure, when you're half-way through retracting your flaps, talking about

where you're going with your passenger, and playing with the GPS.  I'm sure

you'll lose more than 100 feet getting from [engine failure] to [lined up

on the runway].



Yes, the RV can do this turn.  No, we're not all going to be enough on the

ball to make it do that in an unexpected high-stress situation.



-Rob

jpl(at)showpage.org
Guest

Posted: Tue Mar 07, 2006 8:56 am Post subject: Minimum altitude to return to airport

It doesn't matter at what altitude the power fails.  It matters at  

what altitude you have sufficient control of the situation to make  

any further decisions.



If it takes you a half second or 5 seconds to respond, it doesn't  

matter.  Once you have control of the situation, then you check your  

altitude for your minimum turn-back altitude.



-Joe



do not archive



On Mar 7, 2006, at 10:28 AM, Rob Prior (rv7) wrote:



 	  Quote: 	
		   



 And again, as others have pointed out, this was a contrived  

 situation.  The

 pilot briefed and prepared for an engine out on takeoff, and  

 everything

 went according to plan.



 Try the same thing on a climbout when you're not expecting an engine

 failure, when you're half-way through retracting your flaps,  

 talking about

 where you're going with your passenger, and playing with the GPS.   

 I'm sure

 you'll lose more than 100 feet getting from [engine failure] to  

 [lined up

 on the runway].



 Yes, the RV can do this turn.  No, we're not all going to be enough  

 on the

 ball to make it do that in an unexpected high-stress situation.



 -Rob

ogoodwin(at)comcast.net
Guest

Posted: Tue Mar 07, 2006 11:35 am Post subject: Minimum altitude to return to airport

That is the clearest and most well thought out post in this whole thread.



Olen

do not archive



 -------------- Original message ----------------------

From: Joseph Larson <jpl(at)showpage.org>

 	  Quote: 	
		   

 

 It doesn't matter at what altitude the power fails.  It matters at  

 what altitude you have sufficient control of the situation to make  

 any further decisions.

 

 If it takes you a half second or 5 seconds to respond, it doesn't  

 matter.  Once you have control of the situation, then you check your  

 altitude for your minimum turn-back altitude.

 

 -Joe

 

 do not archive

 

 On Mar 7, 2006, at 10:28 AM, Rob Prior (rv7) wrote:

 

 > 

 >

 > And again, as others have pointed out, this was a contrived  

 > situation.  The

 > pilot briefed and prepared for an engine out on takeoff, and  

 > everything

 > went according to plan.

 >

 > Try the same thing on a climbout when you're not expecting an engine

 > failure, when you're half-way through retracting your flaps,  

 > talking about

 > where you're going with your passenger, and playing with the GPS.   

 > I'm sure

 > you'll lose more than 100 feet getting from [engine failure] to  

 > [lined up

 > on the runway].

 >

 > Yes, the RV can do this turn.  No, we're not all going to be enough  

 > on the

 > ball to make it do that in an unexpected high-stress situation.

 >

 > -Rob

 >

 >

halbenjamin(at)aol.com
Guest

Posted: Tue Mar 07, 2006 2:14 pm Post subject: Minimum altitude to return to airport

Hi Doug,

 

Glad to see you're back in fray...Hope you stick around!

 

Hal Benjamin

RV-4 Fuselage

Long Island, NY

Do not archive 

 

--

rcrosley(at)adelphia.net
Guest

Posted: Wed Mar 08, 2006 8:53 am Post subject: Minimum altitude to return to airport

This thread on "returning to the airport" has been interesting but very academic.  Maybe the average guy can do a 180 and not stall, but there is a lot more going on.  First, the transition from power on climb attitude to power off glide attitude is HUGE.  Having lost an engine in a C-120 climbing out of Meadowlark airport (closed now, Huntington Beach CA) I was surprised at how big that transition is.  After getting the nose down it was very obvious that a 180 was out of the question.  I turned 30 degrees left and landed in a plowed field.  But here's the point, if you lose your engine after a normal takeoff roll and climbing to 500 feet, how much runway are you going to have left to land on after making this 180?  Not much.  Probably more ahead of you than behind.  You can tell the guys, "Yep, I made a 180 back to the airport." Probably be best to leave out the part about running off the end of the runway.  Now, put yourself in a Rocket or Pitts.  If you are making that cool 3000 fpm climb and the engine decides to take a break there are altitudes at which it is impossible to get the nose down, establish a glide and land the airplane before hitting the ground, forget the 180 degree turn.  If you just cut off that thrust vector, things happen fast.  Anyway, just some more stuff to think about.

Rich Crosley

RV-8  N948RC

Rosamond, CA

rv8ch

Joined: 10 Jan 2006
Posts: 250
Location: Switzerland

Posted: Wed Mar 08, 2006 9:38 am Post subject: Minimum altitude to return to airport

 	  Quote: 	
		   ...  First, the transition from power on

 climb attitude to power off glide attitude is HUGE.  Having lost an

 engine in a C-120 climbing out of Meadowlark airport (closed now,

 Huntington Beach CA) I was surprised at how big that transition is.


	


So true!  If you don't believe Rich, go out and try it, at

altitude.  Simulate a climbout just after takeoff, then

chop the power.  Wow.  The more power you have, the more

dramatic the difference, assuming a Vx type climb.



-- 

Mickey Coggins

http://www.rv8.ch/

#82007 finishing

do not archive

_________________
Mickey Coggins
http://www.rv8.ch/

jjessen(at)rcn.com
Guest

Posted: Wed Mar 08, 2006 9:54 am Post subject: Minimum altitude to return to airport

Energy management and relative wind is what it's all about, besides having

the ability under extreme duress to figure it all out in time.  For me,

it'll be upset training in the future when I can afford it, just to better

understand what all is going on.  In the meantime, I will make sure I know

what my straight ahead options are and prepare for that.  I'm not yet

skilled enough to even think about turning back given the scenario being

discussed on this thread.  



A Navion that took off in full view of myself and a few others ran into this

exact situation.  Lost engine around 500'.  Two souls on board.  Great

pilot.  All kinds of hours and experience, but by the time he kicked into

mental gear there was no runway left to put it down.  He managed to turn it

almost 180, but landed off airport in a nursery full of 3' high evergreen

trees.  If he hadn't been skilled enough to do this, the souls would

probably have gone elsewhere, but as it turned out, he and his wife made it

okay, after multiple bones being broken and a stay in the hospital.  I've

stood and looked at that end of the runway a great deal since then and have

come to the conclusion I would not have made it. 



When flying out of White Plains, a check ride CFI asked what I would do if

we lost power on take off.  I told him my plan that day would be to go

straight ahead, probably try to make the lake that was across a freeway and

slightly to the left of the runway.  He said he'd rather the freeway, which

I thought rather selfish, given the traffic there would create more carnage.

Neither one of us said turn back.  



I think that practicing such maneuvers is appropriate, at safe altitudes.

Practicing glides, too.  Practice it all.  Practice.  Practice.  Practice.

And when you take off have that engine out scenario and decision points

firmly in mind...in terms of your ability and skill.  Mine for now is

straight ahead.  Hopefully I'll be able to have a few other options as I

become a more skilled pilot.  



John Jessen

  40328 (empennage)



--

bartrim(at)gmail.com
Guest

Posted: Wed Mar 08, 2006 5:26 pm Post subject: Minimum altitude to return to airport

I've been resisting the urge to make a reply as I don't have the time to do

much more than lurk these days, but here goes....

	I really appreciate the info and discussion on this topic as I too believe

there are no absolutes in this decision making process. I did most of my

flight training in my own RV9 with a good friend of mine as instructor. He

initially endlessly drilled into my head to always land straight ahead in

event of power failure on T/O, but as training progressed he began to throw

a few extra scenarios at me. The terrain in northern BC demands it. One

little grass strip that we practiced on has a deep ravine at the end of the

runway. Enough altitude and you can turn back or make it to the other side.

Not enough and your best hope was to turn and try to crash along the bottom.

Not very appealing.

	But allot of thought has gone into a particular strip that I used to fly

out of (as a pax), when I was a hunting guide. 2000' grass with mountains on

3 sides and a glacial fed lake on the end. You always had to T/O over the

lake regardless of wind direction. This lake is very remote so possibility

of rescue from boaters is almost non-existent in case of a water landing.

Help from anywhere out there is unlikely. (kinda like in the movie "The

Edge"... lotsa grizz too!) Every trip I ever had out of there was in a fully

loaded C172 that seemed to use every available inch of runway before we

would struggle out over the lake for a few miles until we gained enough

altitude to safely fly through a mountain pass. Turning back there was

certainly not an option but all other alternatives were also extremely grim.

Fortunately it has never been an issue.

	Time has been at a premium these last few years, preventing me from

returning there but as I'm currently just finishing up my 5th and final year

of tech school I expect to soon be resuming some of these activities, but

this time with my own plane. As my RV9 has far greater climb rate and uses

far less runway, I expect to have more options in case of emergency.

Everytime I fly out of there I will be expecting that engine to fail and

will include in my preflight the exact min. altitude required for a 180 back

to the strip or as close to it as possible.

	If I keep my plane in top mechanical shape then hopefully it will never

happen, but it is an experimental plane with an experimental engine, so by

keeping myself in top physical and mental condition then god willing, I will

have the strength and skill to accomplish something that I would never do at

that perfect airport with a farmers field at the end of each runway (kinda

like my home field .

	I have limited flight experience so I don't like to disagree with

experienced voices such as Doug, but I feel that everyone that fly's in

areas of rugged terrain should be aware of exactly how much altitude they

require to make a 180 and be mentally prepared for it at all times to reduce

the "oh s***" time lag, and the judgment to recognize that a straight in

approach is still better for most cases. But it's not absolute.



Todd Bartrim

Turbo 13B RV-9



 	  Quote: 	
		   It's a rehash.  We all know it's risky and we all know in most

 cases you'd be better off  landing in that near mythically

 perfect field that's almost always mythically conveniently

 located right off the end of almost all airports in the world.



 Nobody ever takes off having to fly out over open water

 http://www.airnav.com/airport/KMCD



 and nobody ever has to take off right over the dense city

 http://www.airnav.com/airport/KVNY



 yep, there's just no reason to ever want to kill yourself turning

 back when you can sometimes just as easily kill yourself going

 straight ahead....

bartrim(at)gmail.com
Guest

Posted: Thu Mar 09, 2006 10:44 pm Post subject: Minimum altitude to return to airport

I've been resisting the urge to make a reply as I don't have the time to do

much more than lurk these days, but here goes....

	I really appreciate the info and discussion on this topic as I too believe

there are no absolutes in this decision making process. I did most of my

flight training in my own RV9 with a good friend of mine as instructor. He

initially endlessly drilled into my head to always land straight ahead in

event of power failure on T/O, but as training progressed he began to throw

a few extra scenarios at me. The terrain in northern BC demands it. One

little grass strip that we practiced on has a deep ravine at the end of the

runway. Enough altitude and you can turn back or make it to the other side.

Not enough and your best hope was to turn and try to crash along the bottom.

Not very appealing.

	But allot of thought has gone into a particular strip that I used to fly

out of (as a pax), when I was a hunting guide. 2000' grass with mountains on

3 sides and a glacial fed lake on the end. You always had to T/O over the

lake regardless of wind direction. This lake is very remote so possibility

of rescue from boaters is almost non-existent in case of a water landing.

Help from anywhere out there is unlikely. (kinda like in the movie "The

Edge"... lotsa grizz too!) Every trip I ever had out of there was in a fully

loaded C172 that seemed to use every available inch of runway before we

would struggle out over the lake for a few miles until we gained enough

altitude to safely fly through a mountain pass. Turning back there was

certainly not an option but all other alternatives were also extremely grim.

Fortunately it has never been an issue.

	Time has been at a premium these last few years, preventing me from

returning there but as I'm currently just finishing up my 5th and final year

of tech school I expect to soon be resuming some of these activities, but

this time with my own plane. As my RV9 has far greater climb rate and uses

far less runway, I expect to have more options in case of emergency.

Everytime I fly out of there I will be expecting that engine to fail and

will include in my preflight the exact min. altitude required for a 180 back

to the strip or as close to it as possible.

	If I keep my plane in top mechanical shape then hopefully it will never

happen, but it is an experimental plane with an experimental engine, so by

keeping myself in top physical and mental condition then god willing, I will

have the strength and skill to accomplish something that I would never do at

that perfect airport with a farmers field at the end of each runway (kinda

like my home field .

	I have limited flight experience so I don't like to disagree with

experienced voices such as Doug, but I feel that everyone that fly's in

areas of rugged terrain should be aware of exactly how much altitude they

require to make a 180 and be mentally prepared for it at all times to reduce

the "oh s***" time lag, and the judgment to recognize that a straight in

approach is still better for most cases. But it's not absolute.



Todd Bartrim		"chance favours the prepared mind"	Louis Pasteur

Turbo 13B RV-9



 	  Quote: 	
		   It's a rehash.  We all know it's risky and we all know in most

 cases you'd be better off  landing in that near mythically

 perfect field that's almost always mythically conveniently

 located right off the end of almost all airports in the world.



 Nobody ever takes off having to fly out over open water

 http://www.airnav.com/airport/KMCD



 and nobody ever has to take off right over the dense city

 http://www.airnav.com/airport/KVNY



 yep, there's just no reason to ever want to kill yourself turning

 back when you can sometimes just as easily kill yourself going

 straight ahead....

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