Auto conversions & gear boxes

Bob

Your right

I posted a follow on to thread covering essentially what you said and
it never made it? I have had several disappeared like that and need to
find out what is happening. I thought at first someone was going in
and deleting my posts but I normally don't get into a Peeing contest
with most posters and need to be censored ).

In any event, glad you posted so some of the young ones will know what
happened a long time ago in a land far away )

Big John

On Wed, 25 Feb 2004 10:37:57 -0500, "Bob Chilcoat"
wrote:

According to Warren Bode in his definitive book on the P-38, the bob weights
in the center of the elevator were mandated by the Army after one of the
YP-38's shed its tail in a dive. Further dive tests seemed to indicate that
the problem was tail flutter at certain speeds. The bob weights were added
but did not solve the problem. Wind tunnel tests eventually traced the
"flutter" problem to buffeting from turbulence off the joint between the
wing and the center fuselage pod. After a fillet was added to soften this
joint, the "flutter" problem disappeared, but the Army would not let Johnson
remove the bob weights. He hated them (the elevator was already
counterbalanced by concealed weights in the tail cones) and felt that their
only contribution was to kill a few pilots who hit them in bailouts. The
"compressability tuck" problem was investigated at the same time, but was
only solved by means of the dive brakes that were added to the P-38J-25-LO
and subsequent models. As it turned out, the compressability problem could
not occur in any P-38's if dives were initiated below 25,000 feet. Since
most P-38 operations during the war were below that altitude, few pilots
encountered the problem in combat.

John,

I saw your post on the same subject after I sent mine. Sorry for the
duplication, but at least yours did make it to my newsreader at least. My
late father (http://users.erols.com/viewptmd/Dad.html) flew the P-38, among
many other aircraft, and we still have his "Flight Manual" for it (and one
for the P-40, and the B-25). I remember reading warnings about
"compressability" in the manual when I was younger, and wondering what that
was all about. My brother in Columbus has the manuals now, so I can't refer
to it.

--
Bob (Chief Pilot, White Knuckle Airways)


"Big John" wrote in message
...

Bob

Your right

I posted a follow on to thread covering essentially what you said and
it never made it? I have had several disappeared like that and need to
find out what is happening. I thought at first someone was going in
and deleting my posts but I normally don't get into a Peeing contest
with most posters and need to be censored ).

In any event, glad you posted so some of the young ones will know what
happened a long time ago in a land far away )

Big John