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You're right, the turn won't be successful started at 200' AGL. From 500' AGL (with fixed pitch prop and engine running in idle) you have enough time/energy to line up on the runway for a normal landing. My priorities are airspeed, continuous monitor; coordination, double check a couple of times; bank angle, comfortable, no burble (approx 60); watch for roll-out/reversal point; check configuration for landing.
My guess is that most of the stall-spin events are caused, not by attempting to return to the departure runway, but by not allowing the aircraft to glide. Even "landing straight ahead" is going to result in a stall-spin, if the pilot won't let the plane glide. Even timid pilots can practice the transition from high-power climb to low/no power glide without risk.
To: lml@lancaironline.net
Date: Fri, 16 May 2008 08:20:13 -0400
From: Sky2high@aol.com
Subject: [LML] Turn back to the Airport after engine failure
Bill and Dom,
Attached is an EXCEL spreadsheet to calculate data about turns - just
fill in the colored entry with the airspeed in Kts.
Using Dom's scenario: At 100 Kts and a 60 degree banked turn, the
turn rate is about 18 degrees per second or about 10 seconds to do a
180. If your prop was left in coarse pitch, the rate of descent is about
1500 fpm (100 KIAS is good enough since our Lancairs best glide is about 105,
depending). In 10 seconds it will have descended 250 feet, 50 feet
below the surface of the planet - Oh, and it will still be 500 feet off the
runway centerline but the wreckage will be easy to find since it will be so
close to the airport.
Bill, your training may kill you by creating false hopes. Of
course, you do practice with the engine turned off, don't you? Prop in coarse
pitch?
Grayhawk
In a message dated 5/15/2008 1:27:58 P.M. Central Daylight Time,
domcrain@tpg.com.au writes:
OK Bill – You’re on the take-off
R/W length 1000 metres (3280’). You’re at say, 200’ passing 100 KIAS Gear is
UP, Flaps retracted – engine dead cuts. Where to?
I think your scenario is fine if you have
a significant amount of breathing gas under, but then – can you still make the
airfield?
Your scenario is seriously debatable, I
believe.
Cheers mate
Dom
VH-CZJ
-----Original
Message-----
From: Lancair
Mailing List [mailto:lml@lancaironline.net] On Behalf Of Bill Kennedy
Sent: Thursday, 15 May 2008 8:39
AM
To:
lml@lancaironline.net
Subject: [LML] Re: Crash, fueling nozzles
and training
I practice these simulated engine
failure turns from time to time. I'd far rather land on or parallel to the
runway than in the whatever off the ends of the runway. There is a big
difference between a maximum performance turn at 100 KIAS and a 60 degree bank
turn. My experience suggests that the turn rate is so fast at max performance,
that timing the rollout becomes a problem. Max performance puts you on the
edge of a stall, so brain overload is a problem too. However, a 60 degree bank
produces a very brisk turn rate without overtaxing my brain. I can still hold
my 100KIAS and time my rollout perfectly.
To reiterate:
1. Max
performance turns at low altitude suck.
2. 60 degree bank turns are easy if
you maintain your airspeed.
3. Practice, or don't plan to do it for real.
The key things are to maintain your airspeed and keep the ball in the
middle.
Almost all say they'd land "straight ahead". Almost all attempt
to return to the airport when it actually happens. The one's who don't
practice often
die.
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