Bomb hits tailplane on release

Ed Rasimus wrote:

Higher speeds mean the store can generate lift (just like any curved
surface.)

IIRC, "curved" is unnecessary here. After all, they do say that, given
enough thrust, a brick will fly, do they not?

On Wed, 23 Jun 2004 17:27:32 +0100, Robert Briggs
wrote:

Ed Rasimus wrote:

Higher speeds mean the store can generate lift (just like any curved
surface.)

IIRC, "curved" is unnecessary here. After all, they do say that, given
enough thrust, a brick will fly, do they not?

Actually, no. Lift is balanced by weight, while thrust opposes drag.
The brick (AKA F-4) would not really "fly", but simply be propelled in
the desired direction. It is the tendency for airflow to accelerate
over a curved surface creating a low pressure area that causes "lift".
The dropped store had better be curved if you want to get lift, since
it isn't supplied with thrust.


Ed Rasimus
Fighter Pilot (USAF-Ret)
"When Thunder Rolled"
Smithsonian Institution Press
ISBN #1-58834-103-8

Ed Rasimus wrote:
Robert Briggs wrote:
Ed Rasimus wrote:

Higher speeds mean the store can generate lift (just like any curved
surface.)

IIRC, "curved" is unnecessary here. After all, they do say that, given
enough thrust, a brick will fly, do they not?

Actually, no. Lift is balanced by weight, while thrust opposes drag.

This assumes more than I wrote.

Can you say "Harrier", for example?

Okay, I didn't have that aeroplane in mind, but I *was* careful not to
specify any particular angle of attack - after all, an "inverted" pass
at an air display is not *exactly* inverted, with the aerofoil acting
against you (in the case of "ordinary" aeroplanes, at any rate).

The brick (AKA F-4) would not really "fly", but simply be propelled in
the desired direction. It is the tendency for airflow to accelerate
over a curved surface creating a low pressure area that causes "lift".
The dropped store had better be curved if you want to get lift, since
it isn't supplied with thrust.

I was also careful to omit any assertion about the aerodynamic stability
of the brick.

In article ,
Ed Rasimus wrote:

On Wed, 23 Jun 2004 17:27:32 +0100, Robert Briggs
wrote:

Ed Rasimus wrote:

Higher speeds mean the store can generate lift (just like any
curved surface.)

IIRC, "curved" is unnecessary here. After all, they do say that,
given enough thrust, a brick will fly, do they not?

Actually, no. Lift is balanced by weight, while thrust opposes drag.
The brick (AKA F-4) would not really "fly", but simply be propelled in
the desired direction. It is the tendency for airflow to accelerate
over a curved surface creating a low pressure area that causes "lift".
The dropped store had better be curved if you want to get lift, since
it isn't supplied with thrust.

....except when you're looking at something like the B-70 "waverider"
technique, where the underside of the plane provides compression lift,
without providing classical Bernoulli-type lift.

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

To be 'technically' correct... a wing with camber (curved) can generate
lift at zero angle of attack. A symmetric airfoil (such as a flat brick)
cannot, it must be at a positive angle of attack to generate lift (but the
point is... it CAN). Both generate lift (positive C sub L) but at different
AOA. At 'normal' airspeeds the coefficient of lift may not be sufficient
for a brick to generate enough lift to fly, but then again if the airspeed
was high enough....

Here's some reading on the subject....

"...Almost any relatively flat surface could be made to generate some lift.
In fact, a perfectly flat thin plate will do the job. If you don't believe
that, try out any of a number of simple little balsa-wood hand launched
model gliders. Most of them have flat wing sections, and they fly. The flat
plate, then, is probably the simplest of airfoil sections, as shown in
Figure 5..."

From the following site

http://142.26.194.131/aerodynamics1/Basics/Page4.html

Mark

"Robert Briggs" wrote in message
...
Ed Rasimus wrote:

Higher speeds mean the store can generate lift (just like any curved
surface.)

IIRC, "curved" is unnecessary here. After all, they do say that, given
enough thrust, a brick will fly, do they not?

Robert Briggs wrote:
Richard Brooks wrote:
Paul Housley wrote:

A while ago, I saw video footage of a bomb being released from a
fighter-bomber under test conditions. It was on an aviation
documentary. The high speed camera then shows it climb up and
destroy the tailplane. I don't think they quite got their
trajectory calcs right!

This shows up towards the end of a documentary called Dambusters,
which has been seen on UKs Channel 4.

The Lanc may have had guns, but that doesn't make it a fighter-bomber.


I'm sorry, I didn't give enough information. The footage of the American
aircraft disintegrating, being sought was at the end of the hour-long
documentary which included photos with a German officer standing beside a
mine which had not exploded, interviews with one of the tower sentries,
interviews with people who lived near the dams, German and American
variants, etc . It's been the best documentary on the whole bouncing bomb
idea

Richard.

"Richard Brooks" wrote in message
...
Robert Briggs wrote:
Richard Brooks wrote:
Paul Housley wrote:

A while ago, I saw video footage of a bomb being released from a
fighter-bomber under test conditions. It was on an aviation
documentary. The high speed camera then shows it climb up and
destroy the tailplane. I don't think they quite got their
trajectory calcs right!

This shows up towards the end of a documentary called Dambusters,
which has been seen on UKs Channel 4.

The Lanc may have had guns, but that doesn't make it a fighter-bomber.


I'm sorry, I didn't give enough information. The footage of the American
aircraft disintegrating, being sought was at the end of the hour-long
documentary which included photos with a German officer standing beside a
mine which had not exploded, interviews with one of the tower sentries,
interviews with people who lived near the dams, German and American
variants, etc . It's been the best documentary on the whole bouncing bomb
idea

The only US aircraft that I am aware of that practiced and executed skip
bombing missions during WWII was the B-25, principally in the Southwest
Pacific theater; could that perhaps be the type of aircraft you were looking
for?

Brooks


Richard.

Robert Briggs wrote:
Richard Brooks wrote:
Paul Housley wrote:

A while ago, I saw video footage of a bomb being released from a
fighter-bomber under test conditions. It was on an aviation
documentary. The high speed camera then shows it climb up and destroy
the tailplane. I don't think they quite got their trajectory calcs
right!

This shows up towards the end of a documentary called Dambusters, which
has been seen on UKs Channel 4.

The Lanc may have had guns, but that doesn't make it a fighter-bomber.

That said, without the "fighter-" qualification (and substituting
"damage" for "destroy"), the description does indeed suggest the old
Bouncing Bomb trials.

Correction: I had a quick look at the Channel 4 DVD overnight, which
showed the mine staying quite close to the surface - but the Lanc was
low enough that the initial splash knocked some bits off the tail
section.

Robert Briggs wrote:
Robert Briggs wrote:
Richard Brooks wrote:
Paul Housley wrote:

A while ago, I saw video footage of a bomb being released from a
fighter-bomber under test conditions. It was on an aviation
documentary. The high speed camera then shows it climb up and
destroy the tailplane. I don't think they quite got their
trajectory calcs right!

This shows up towards the end of a documentary called Dambusters,
which has been seen on UKs Channel 4.

The Lanc may have had guns, but that doesn't make it a
fighter-bomber.

That said, without the "fighter-" qualification (and substituting
"damage" for "destroy"), the description does indeed suggest the old
Bouncing Bomb trials.

Correction: I had a quick look at the Channel 4 DVD overnight, which
showed the mine staying quite close to the surface - but the Lanc was
low enough that the initial splash knocked some bits off the tail
section.

Hi Robert, I didn't notice that but it was an American aircraft that just
turned to flotsam after a second or two in the footage that wsa shown later
in the documentary.

It kind of reminds me of a short clip shown in (IIRC) an Australian
production called Broadcast which was about the last days of guys running
around with cine-cameras for the film theatre newsreels.

Right at the start is shows lots of news clips and one that stands out is of
three Beauforts doing a low fly-past over a bay and as they passed the ship
where the film was being made, one of hte Beauforts took a sharp climb,
tearing the tail of one of the others with them both crashing into the
water.

Amazing and I bet there are lots of bits of film we haven't seen. I also
wonder if anyone cine-filmed an airshow in Britain where a hurricane
accidentally fired into the crowd as it made a pass ?


Richard.

"Richard Brooks" wrote in message
...
Robert Briggs wrote:
Robert Briggs wrote:
Richard Brooks wrote:
Paul Housley wrote:

A while ago, I saw video footage of a bomb being released from a
fighter-bomber under test conditions. It was on an aviation
documentary. The high speed camera then shows it climb up and
destroy the tailplane. I don't think they quite got their
trajectory calcs right!

This shows up towards the end of a documentary called Dambusters,
which has been seen on UKs Channel 4.

The Lanc may have had guns, but that doesn't make it a
fighter-bomber.

That said, without the "fighter-" qualification (and substituting
"damage" for "destroy"), the description does indeed suggest the old
Bouncing Bomb trials.

Correction: I had a quick look at the Channel 4 DVD overnight, which
showed the mine staying quite close to the surface - but the Lanc was
low enough that the initial splash knocked some bits off the tail
section.

Hi Robert, I didn't notice that but it was an American aircraft that just
turned to flotsam after a second or two in the footage that wsa shown
later
in the documentary.

It kind of reminds me of a short clip shown in (IIRC) an Australian
production called Broadcast which was about the last days of guys running
around with cine-cameras for the film theatre newsreels.

Right at the start is shows lots of news clips and one that stands out is
of
three Beauforts doing a low fly-past over a bay and as they passed the
ship
where the film was being made, one of hte Beauforts took a sharp climb,
tearing the tail of one of the others with them both crashing into the
water.

Amazing and I bet there are lots of bits of film we haven't seen. I also
wonder if anyone cine-filmed an airshow in Britain where a hurricane
accidentally fired into the crowd as it made a pass ?


Richard.

The aircraft was an American A26 and the weapon was a "Highball"
anti-shipping mine that was also indended for use on Mosquitos.

John