"... improves the glide performance."
Gary, do you have any estimate of the expected descent rate with both engines out and both props in "low drag" position?
With most twins you don't lose both engines at exactly the same time
because the engines are being fed from two separate tanks and they don't
hit empty at exactly the same time. Earhart's plane was different and
the fuel system did supply both engines from the same tank so AE would
lose both engines at the same time when she ran out of fuel. From repoort 487
I computed that her max L/D ratio was 11.89 which would be approximately her
glide ratio but it would be something less, due to the drag of the windmilling
propellers so a ratio of 10 to 1 is reasonable to assume. At her empty
weight, the best glide speed would be about 100 mph so this means she
would be going down at a rate of 10 mph which is 14.7 feet per second.
One thousand feet divided by 14.7 feet per second means the airplane
would splash down in 68 seconds. Different reasonable assumptions for
glide ratio and best glide speed won't make a big difference in the time
to splash.
Every book that discusses ditching recommend making a controlled
ditching prior to using the last drop of fuel. With power still
available you can choose the best heading that is parallel to the swells
and you can adjust your touch down point to avoid hitting the face of a
wave and can land on top of the swells which gives you the best chance
for survival. According to AFM 64-6,
Aircraft Emergency Procedures Over
Water, with winds less than 25 knots you do not try to land into the
wind but land parallel to the swells. If the swells are not
perpendicular to the wind then choose the heading that is parallel to
the swells and has the larger headwind component. Only with a wind speed
greater than 35 knots should you select a heading directly into the
wind. Between 25 and 35 knots you choose an intermediate heading.
gl