B-17s at Low Level

Subject: B-17s at Low Level
From: "M. H. Greaves"
Date: 3/14/04 3:40 AM Pacific

"and i hope you didnt bring any bombs back"!!

Nope never did.


Arthur Kramer
344th BG 494th BS
England, France, Belgium, Holland, Germany
Visit my WW II B-26 website at:
http://www.coastcomp.com/artkramer

Not that it applies to the B-17, but I would think that unless hydraulic
flaps were preloaded (spring or other or were heavy) to extend without
hydraulic pressure, the airflow would keep them retracted until airspeed
decreased or even until the a/c got on the ground. As for the gear,
unless it was kept in the retracted position by hydraulic pressure
alone, as on many modern light aircraft, the mechanical uplocks would
keep the gear up. Also, depending on gear door operation, the airflow
could very well keep the doors closed, or at least partially closed,
until airspeed decreased. Lack of pressure could also just allow the
doors to stay closed & the gear stay up regardless, depending upon how
they're actuated.

In article ,
Dale writes:
In article ,
"Gord Beaman" ) wrote:


Dale, with some time on them I'm sure that you'd agree that when
limping home on two engines having your flaps or gear down would
very likely ruin your chances of ever getting home, right?.

At the weights I flew the airplane it performed fairly well on two
engines, even so why stack the deck against yourself by adding drag. G
On a hot day, or high field elevation having the gear/flaps out could
certainly make a difference in the outcome.

There was a bunch of discarded ammo and .50s from the continent to
England for a reason. G

And Ball Turrets, as well. If you're hedgehopping across Belgium,
it's a fiar bet that if you could, you'd jettison the Ball Turret.
That would leave off something arounf 1500#. IIRC, the procedure was
to pull the traversing motor (that drives the pinion that engafges the
traversing ring gear that's on the edge of the fuselage hole for the
turret, and undo the retainer that holds the spindle for the turret
yoke to the fuselage bracket. Takes about 5 minutes with a wrench,
hammer, and chisel. The end result would be no turret, the fuselage
mounting bracket in place, and teh ring gear at the turret opening.


--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster

My question is, would a B-17 have its landing flaps deployed at all at this
lower speed and altitude if it was not landing, just hedge-hopping home? And
if so, how much?

no, the flaps on the -17 were mostly drag devices, and did not help generate
lift.
Matt Gunsch,
A&P,IA,Private Pilot
Riding member of the
2003 world champion drill team
Arizona Precision Motorcycle Drill Team
GWRRA,NRA,GOA

Unless of course the hydraulic system has been shot out in which case both
flaps and landing gear would be down. As I vaguely remember it that
hydraulic
sytem in a B-17 worked off one engine.I don't remember which one. But I
might
be wrong about that,

You are, the only hydraulics on a -17 are cowl flaps and brakes, everything
else is electric. Boeing was even thinking ahead, all the gear and bombay
motors were the same.
Matt Gunsch,
A&P,IA,Private Pilot
Riding member of the
2003 world champion drill team
Arizona Precision Motorcycle Drill Team
GWRRA,NRA,GOA

In article ,
(N329DF) wrote:

no, the flaps on the -17 were mostly drag devices, and did not help generate
lift.

Well, they help a little. Book shortfield procedure calls for 10-20
degrees of flap. Flaps do allow you to liftoff a little sooner/slower.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

(The Enlightenment) wrote:

Engine Oil pressure was used to set pitch on the propeller. Engine
oil loss could lead to a runaway propellor.


Well, it wouldn't overspeed for very long at any rate!...
--

-Gord.

wrote:

Not that it applies to the B-17, but I would think that unless hydraulic
flaps were preloaded (spring or other or were heavy) to extend without
hydraulic pressure, the airflow would keep them retracted until airspeed
decreased or even until the a/c got on the ground. As for the gear,
unless it was kept in the retracted position by hydraulic pressure
alone, as on many modern light aircraft, the mechanical uplocks would
keep the gear up. Also, depending on gear door operation, the airflow
could very well keep the doors closed, or at least partially closed,
until airspeed decreased. Lack of pressure could also just allow the
doors to stay closed & the gear stay up regardless, depending upon how
they're actuated.

Quite right, I forgot to mention that...
--

-Gord.

Dale wrote:

In article ,
(N329DF) wrote:

no, the flaps on the -17 were mostly drag devices, and did not help generate
lift.

Well, they help a little. Book shortfield procedure calls for 10-20
degrees of flap. Flaps do allow you to liftoff a little sooner/slower.

Of course, most a/c use some flaps for takeoff but it would have
only a detrimental effect (I'm pretty sure) at cruise...I know
two pilots who will swear on their mothers' grave to this....

Cruising along on a 'boring holes' exercise (quite boring indeed)
a couple pilots and I were discussing the possibilities of
this...my position was that even a couple degrees of flap would
be detrimental, one of the pilots was 'certain' that it would
help, the other was undecided. We had quite a discussion going
and ended up with a substantial bet between I and the sure guy,
to be paid in beer at the next squadron bash. (all that one can
drink - woohoo)

We were at 'range power', an airspeed that produces maximum range
at the particular weight. we had been there for long enough that
our airspeed was stable, co-jo inched down a couple degrees of
flap (very slowly and carefully) I waited a few seconds then
carefully inched the cowl flaps open quite a few degrees.

Airspeed slowly decreased...co-jo inched the flaps back up and I
followed by inching the cowl flaps closed. We did this several
times till he was convinced. (the pilots cannot see the cowl flap
position gauges nor the switches which are behind them on the
F/E's panel on the Argus. I never did tell them different. Fun.
--

-Gord.

In article ,
"Gord Beaman" ) wrote:



Airspeed slowly decreased...co-jo inched the flaps back up and I
followed by inching the cowl flaps closed. We did this several
times till he was convinced. (the pilots cannot see the cowl flap
position gauges nor the switches which are behind them on the
F/E's panel on the Argus. I never did tell them different. Fun.


You're a baaaad boy!! G

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html