Premium on Safety - Issue 41, 2021 - 8

ASI MESSAGE
An Impossible Turn?
Reality Check on Turnbacks
The March crash of a
Beechcraft Bonanza A36
in Pembroke Pines, Florida,
resurfaced debate about
the " turnback, " an engineout
course reversal shortly
after takeoff to land in the
opposite direction on the
departing runway. Initial NTSB reports indicate the pilot of the
Bonanza attempted a turnback with disastrous results.
In April, the AOPA Air Safety Institute flew profiles at Martinsburg
(MRB), West Virginia's 8,800-foot-long, 150-foot-wide runway to
determine the feasibility of turnbacks.
The profile involved climbing between VX
and VY with full power
to a predetermined altitude, cutting power to idle, delaying
three seconds to simulate a startle period, then pushing to best
glide while entering a 45-degree-bank turn back to the runway.
Our lineup included me in my 150-horsepower, 1993 Piper
PA-18 Super Cub with full gas; AOPA Pilot Editor at Large Dave
Hirschman solo in his Van's RV-4 fully fueled; Hirschman and
AOPA Vice President of Flight Operations Dave Roy in a 1972
Beechcraft Bonanza A36 with a 300-horsepower Continental
IO-550, full gas, and 40 pounds of baggage; and AOPA Director
of Flight Operations Luz Beattie alone in a fully fueled 1978
Cessna 172N.
Prior to the exercise, we all climbed to altitude and practiced
stalls, including stalls in 45 degrees of bank, to calibrate the
actual stall speeds at play during our turnback exercise. We then
established our minimum required turnback altitude using airline
pilot and CFI Brian Schiff's technique. We set a climb profile, cut
the power to idle, and began an idle power, 45-degree-bank turn
at best glide for 360 degrees, noting the altitude lost.
With stall numbers and expected turnback altitude requirements
freshly established, we each flew three profiles in near-perfect
conditions: cool, sunny morning, light winds, low density altitude.
Please see the accompanying video-Reality Check: The Runway
Behind You-in which we documented the results and our
conclusions (below).
Our takeaway is that in certain aircraft with good climb rates
and glide ratios, flown by proficient pilots who've trained for the
maneuver, a turnback is a viable option. Aircraft with poor poweroff
glide performance in a turn are unlikely to make a turnback
at any altitude. Pilots flying these aircraft using typical departure
and climbout profiles should eliminate turnbacks as an option for
engine failure on takeoff.
Variables like wind, temperature, density altitude, and technique
could affect these results, but not enough to substantially
improve our outcomes. Please don't fly this exercise solo in an
attempt to prove us wrong or confirm our results. We've lost
pilots training in these maneuvers due to the high potential for
an uncoordinated stall and spin in the turnback. Fly with a CFI,
at altitude first and determine your strategy in the event of an
engine failure on takeoff.
Go fly.
Richard G. McSpadden, Jr.
Senior Vice President, AOPA Air
Safety Institute
Reality Check: The Runway
Behind You
Is the " impossible turn " in a single-engine airplane after all possible? Ask a
group of pilots and you'll stoke a passionate debate among opponents and
proponents of what is known as the " 180-degree turnback " to the departure
runway after engine failure on takeoff.
We investigated the disputed turnback theories, using a Piper PA-18
Super Cub, a Van's RV-4, a Cessna 172N, and a Beechcraft Bonanza
A36. Our study was conducted by highly experienced and proficient
pilots flying predetermined profiles in near-perfect conditions. But the
different results of turning back to the runway were surprising for each
of us flying these profiles. You'll see why in the Reality Check video
accompanying this story. Click the multimedia button to watch.
8
https://www.captainschiff.com/
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