R/C Flying - B52 b.jpg (1/1)

[Mitchell Holman[_2_]]

[Robert Moore]

Mitchell Holman wrote
> begin 644 B52 b.jpg

OK Mitchell....where's the video of this event? :)

Bob Moore

[Mitchell Holman[_2_]]

Robert Moore > wrote in
. 15.205:

> Mitchell Holman wrote
>> begin 644 B52 b.jpg
>
> OK Mitchell....where's the video of this event? :)
>
> Bob Moore


Good question. If one exists I don't want to see it.
Too sad to see so much work end up as splintered balsa...

[Mike Proctor]

Robert Moore wrote:
> Mitchell Holman wrote
>> begin 644 B52 b.jpg
>
> OK Mitchell....where's the video of this event? :)
>
> Bob Moore


http://www.youtube.com/watch?v=dxp4qYC9ZtU

[Rusty Knuckle]

Sometimes I just can't help but smile.

RK

[Scubabix]

The video of this crash was eerily like the crash of the B-52 at Fairchild
AFB a few years back.

Rob

"Mitchell Holman" > wrote in message
...

[Morgans[_2_]]

"Scubabix" > wrote in message
...
> The video of this crash was eerily like the crash of the B-52 at Fairchild
> AFB a few years back.

That is because the cause for each of the crashes was somewhat the same.

The Buff did not use regular ailerons, as you would normally think of them.
The flexibility of the wing would twist when a normal aileron input was
applied, and would actually give the opposite roll reaction that was
expected. The aileron was acting like a boost tab, in sorts.

The solution was to control roll by having a spoiler instead of an aileron,
so that if you wanted to roll right, the right spoiler went up, that side
lost some lift, and the aircraft rolls. It was also good to prevent adverse
yaw.

The only problem with that type of control roll, was that if a critical bank
angle was exceeded, the roll was unrecoverable. Your were going to crash,
period.

The full sized crash was being piloted by a senior pilot who was known as a
cowboy, and exceeded various flight parameters, frequently. Some crew would
not fly with him. He pulled his steep bank trick one too many times, and
did not get away with it.

The RC model might have gotten too steep, in a normal flight pattern, but I
think what happened was that the overcast sky messed up the pilot's
orientation clues, and he banked steeper, rather that flattening it out.
I've done it, and about anyone who flies RC has also done it, and gotten it
back into control. With the model Buff, getting that steep put you into an
unrecoverable area of the flight envelope. Boom, was the final result.
--
Jim in NC

[ABLE_1[_2_]]

> The RC model might have gotten too steep, in a normal flight pattern, but
> I think what happened was that the overcast sky messed up the pilot's
> orientation clues, and he banked steeper, rather that flattening it out.
> I've done it, and about anyone who flies RC has also done it, and gotten
> it back into control. With the model Buff, getting that steep put you
> into an unrecoverable area of the flight envelope. Boom, was the final
> result.
> --
> Jim in NC

Sorry to jump in here.

But as I recall the discussion at the time of the RC crash it was due to the
"dreaded downwind turn" that plagues some RC pilots at times.

But no matter the real reason the outcome is the same.

Les

[Morgans[_2_]]

"ABLE_1" > wrote

> But as I recall the discussion at the time of the RC crash it was due to
> the "dreaded downwind turn" that plagues some RC pilots at times.
>
> But no matter the real reason the outcome is the same.

Oh no! The dreaded downwind turn!!!

Of course, this is a subject that has been possible the most discussed of
any subject. I tend to go with the aerodynamicist that says that a downwind
turn problem is impossible to be a problem.

I can believe there will be a problem if the pilot does not correctly keep
his speed up when he turns downwind, but if a plane was flying when it
started the turn, and the same airspeed is maintained, there will not be a
crash.
--
Jim in NC

[Bob Harrington]

"Morgans" > wrote in
:

>
> "ABLE_1" > wrote
>
>> But as I recall the discussion at the time of the RC crash it was due
>> to the "dreaded downwind turn" that plagues some RC pilots at times.
>>
>> But no matter the real reason the outcome is the same.
>
> Oh no! The dreaded downwind turn!!!
>
> Of course, this is a subject that has been possible the most discussed
> of any subject. I tend to go with the aerodynamicist that says that a
> downwind turn problem is impossible to be a problem.
>
> I can believe there will be a problem if the pilot does not correctly
> keep his speed up when he turns downwind, but if a plane was flying
> when it started the turn, and the same airspeed is maintained, there
> will not be a crash.

Indeed, the plane's frame of reference is the atmosphere, not the ground.
Unless it runs into some hellacious shear, the airspeed will not change in
the turn any more than it would in a pefectly static air mass.

Kind of like the plane taking off from a conveyor belt myth that was so
solidly busted on 'Mythbusters'...

Bob ^,,^

[ABLE_1[_2_]]

> I can believe there will be a problem if the pilot does not correctly keep
> his speed up when he turns downwind, but if a plane was flying when it
> started the turn, and the same airspeed is maintained, there will not be a
> crash.
> --
> Jim in NC


However is it not true that perception of airspeed WITHOUT a indicator other
than ones eye is very difficult when standing on the ground than it is at
any other time???


Les

[Morgans[_2_]]

> However is it not true that perception of airspeed WITHOUT a indicator
> other
> than ones eye is very difficult when standing on the ground than it is at
> any other time???

Yes, and that is what I was hinting at.

Yet, if the pilot does not reduce throttle, or gain altitude during the
turn, and makes the turn just like he always turns (probably true in most
cases) then there would be no reason to be slowing down, no matter what he
observed with the airspeed.

It is a nice way to cover saying (or not to say) I screwed the pooch, to the
uninformed!
--
Jim in NC

[Scubabix]

> That is because the cause for each of the crashes was somewhat the same.
>
> The Buff did not use regular ailerons, as you would normally think of
> them. The flexibility of the wing would twist when a normal aileron input
> was applied, and would actually give the opposite roll reaction that was
> expected. The aileron was acting like a boost tab, in sorts.
>
> The solution was to control roll by having a spoiler instead of an
> aileron, so that if you wanted to roll right, the right spoiler went up,
> that side lost some lift, and the aircraft rolls. It was also good to
> prevent adverse yaw.
>
> The only problem with that type of control roll, was that if a critical
> bank angle was exceeded, the roll was unrecoverable. Your were going to
> crash, period.
>
> The full sized crash was being piloted by a senior pilot who was known as
> a cowboy, and exceeded various flight parameters, frequently. Some crew
> would not fly with him. He pulled his steep bank trick one too many
> times, and did not get away with it.
>
> The RC model might have gotten too steep, in a normal flight pattern, but
> I think what happened was that the overcast sky messed up the pilot's
> orientation clues, and he banked steeper, rather that flattening it out.
> I've done it, and about anyone who flies RC has also done it, and gotten
> it back into control. With the model Buff, getting that steep put you
> into an unrecoverable area of the flight envelope. Boom, was the final
> result.
> --
> Jim in NC
Thanks Jim, for the explanation of the Buff's flight characteristics. I was
well aware of the reputation of the pilot. There are numerous cases of the
pilot in control killing their crews by doing what they shouldn't. I always
kept that in mind when the pilots I flew with exceeded my comfort zone. Fly
safe.

Rob