In article , Snowbird wrote:
I don't think difference in cruise speed is the issue. If you read
the study carefully, IIRC the vacuum failure was done during climbout
after a missed approach -- a point where the speed difference is
not as large. I believe the same protocol was followed during the
previous simulator study.

The vacuum failure was also done at a high workload point in the
climbout by the looks of things.

In a Cherokee, climbout from a missed approach or takeoff in IMC is
accomplished by going wide open throttle and leaving it there. In a
Bonanza, there's engine management to be done (go from takeoff to climb
power, which involves reducing throttle and prop), and raise the gear.
Also things happen A LOT quicker in the climb in a Bonanza. The Cherokee
in the study was probably climbing out at 800 fpm. The Bonanza was
probably climbing out at around 1600 fpm. (Lightly loaded, the takeoff
power climb rate of our club's S35 Bonanza would exceed 1800 fpm).

This means not only do you have to do more in the Bonanza, you have much
less time to do it in. Also, if you get into an unusual attitude,
relative to a Cherokee, you've got a tremendous amount of power helping
the slippery airframe to accelerate. A pilot who has only marginal
control and is mentally 'maxed out' might be able to pull it off in a
Cherokee. Add the extra tasks of putting the gear up, setting climb
power and climb RPM plus double the climb rate, a pilot who's 'maxed
out' will quite possibly be pushed over the edge.

I note that there are several pairs of planes where the retract
apparently has a higher LOC accident rate than its fixed gear
"brother" yet the handling is pretty much the same and the
speed difference not that great.

If the pilot is already 'maxed out' by operating on partial panel,
the additional task of retracting the gear might be enough to push
them over the edge if they are only marginally in control in the first
place. A bit like the straw that breaks the camel's back.

--
Dylan Smith, Castletown, Isle of Man
Flying: http://www.dylansmith.net
Frontier Elite Universe: http://www.alioth.net
"Maintain thine airspeed, lest the ground come up and smite thee"