Can F-15s making 9G turns with payload?

On Thu, 18 Sep 2003 16:45:14 -0700, "Tarver Engineering"
wrote:


"Mike Marron" wrote in message
.. .
Ed Rasimus wrote:
Chad Irby wrote:

I know there were a couple of cases in Vietnam where F-4s made hard
enough turns to rip the ECM pods off...

Gotta wonder about that, since ECM pods were routinely carried in the
Sparrow missile wells. Can't imagine a situation in which the pods
suspension gear would fail. Don't say it couldn't, simply that I doubt
it.

In 250 combat missions, 150 over NVN where high threat evasions were
most likely, I never, not even once, heard of a structural failure nor
of an inadvertent separation of any piece of equipment off an
aircraft. I'm not saying it couldn't have, simply that I doubt it.

I doubt it too!

I don't know how much an F-4 ECM pod weighs, but I do know that it
would require a hellacious amount of G's to cause the bolts that
fasten the pod to the airframe to fail.

How could you possibly know that?



Math.

In article ,
Scott Ferrin wrote:

On Thu, 18 Sep 2003 16:45:14 -0700, "Tarver Engineering"
wrote:


"Mike Marron" wrote in message
.. .

I don't know how much an F-4 ECM pod weighs, but I do know that it
would require a hellacious amount of G's to cause the bolts that
fasten the pod to the airframe to fail.

How could you possibly know that?

Math.

....and a near-religious faith that new bolts are just as strong as old
bolts, while corrosion never happens and flightline troops never make
mistakes.

Film at 11.

--


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

Chad Irby wrote:
Scott Ferrin wrote:
"Tarver Engineering" wrote:
"Mike Marron" wrote:

I don't know how much an F-4 ECM pod weighs, but I do know that it
would require a hellacious amount of G's to cause the bolts that
fasten the pod to the airframe to fail.

How could you possibly know that?

Math.

...and a near-religious faith that new bolts are just as strong as old
bolts, while corrosion never happens and flightline troops never make
mistakes.

Why y'all respond to the dreaded "tarv troll" is beyond me!
In any event, Chad, you're absolutely correct that flightline troops
make mistakes. But the good folks in St. Louis at the McDonnell
Douglas plant have a few scruples to speak of and you can rest
assurred that they designed the F-4's ECM pod with hamfisted
pilots and/or hairy-assed line mechanics in mind.

With regards to your comments about threaded areas and/or
corrosion possibly weakening the ECM attachment points, as
you know AN hardware comes in a wide variety of different flavors
and anything prone to corrosion is generally cadmium plated.
And AN bolts have "rolled" threads (as opposed to "cut" threads)
which results in a strengthening of the bolt in the thread area.

But once again, doubtful the "brainy" types in St. Louis designed the
ECM pod fasteners to take shear loads in the threaded area
anyway (it is a bad practice to do this with any bolt, AN or
otherwise). From a practical standpoint even if you took took an
AN bolt and clamped it in a vice then punished it with a sledgehammer,
you'd find that you could exceed the yield strength without actually
breaking the bolt as it would stretch or bend quite a bit before
snapping.

The bottom line is that, yeah, I actually DO have a "near-religious
faith" in AN hardware since it's my own butt hanging from one single
solitary AN6-44 bolt when flying my own personal homebuilt aircraft
that's rated to +6, -3 G's. I don't simply wrench on A/C and sign 'em
over to some guinea pig to test fly, I actually fly A/C that I worked
on, modified, or constructed myself. I'm not claiming to have flown
an F-4, but that's how I know that it would require a hellacious
amount of G's to cause the bolts that fasten the ECM pod to the
F-4's airframe to fail.

Film at 11.

Cool. I assume it's a film showing an F-4 ECM pod departing the
airframe in Vietnam as you said?


-Mike Marron
A&P, CFII, UFI (fixed-wing, weightshift, land & sea)

On Fri, 19 Sep 2003 14:49:34 GMT, Mike Marron
wrote:

Why y'all respond to the dreaded "tarv troll" is beyond me!
In any event, Chad, you're absolutely correct that flightline troops
make mistakes. But the good folks in St. Louis at the McDonnell
Douglas plant have a few scruples to speak of and you can rest
assurred that they designed the F-4's ECM pod with hamfisted
pilots and/or hairy-assed line mechanics in mind.

"Hamfisted" crew from Ubon in early 1967 blew a pod off a pylon over
North Vietnam.

And a pod fell off a pylon on a plane taking off at Ubon shortly after
that. No cause was found. The "hairy-assed" line mechanics that loaded
the pod that day were never talked to or questioned about it.

Pods were carried for years hanging from pylons and even the bottom
rack on MERs.
Ever see the two "little" hooks in the pylon that hold bombs and pods
to the pylons?
Take into consideration that bombs and center tanks were dropped to
clean an aircraft up so it could maneuver better. But that pod hung in
there way out from the centerline.

Buzzer wrote:

"Hamfisted" crew from Ubon in early 1967 blew a pod off a pylon over
North Vietnam.

And a pod fell off a pylon on a plane taking off at Ubon shortly after
that. No cause was found.

Interesting. I'm somewhat surprised that Ed Rasimus never heard of
these incidents during his 250 combat missions in SEA in Thuds and
Phantoms. In any event, I simply "doubted" that it could happen, not
that it unequivocally did not happen.

-Mike Marron

In article ,
Buzzer wrote:

"Hamfisted" crew from Ubon in early 1967 blew a pod off a pylon over
North Vietnam.

And a pod fell off a pylon on a plane taking off at Ubon shortly after
that. No cause was found. The "hairy-assed" line mechanics that loaded
the pod that day were never talked to or questioned about it.

If you didn't do it just right, the missile well adapter for ECM pods
wouldn't lock. Once it was pinned in, the thing wasn't going to come
out without some sort of serious failure.

Pods were carried for years hanging from pylons and even the bottom
rack on MERs.
Ever see the two "little" hooks in the pylon that hold bombs and pods
to the pylons?
Take into consideration that bombs and center tanks were dropped to
clean an aircraft up so it could maneuver better. But that pod hung in
there way out from the centerline.

After a couple of problems in Vietnam, they made it impossible for
pilots to jettison ECM pods.

An apocryphal story they used to tell us was that some fighter jock was
trying to kill a boat on a river. He dropped bombs. Missed. He used
up all of his 20mm. Missed. So he went in on a run and jettisoned the
pod. Hit. one $5,000 boat for a million dollar pod...

--


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

On Fri, 19 Sep 2003 18:05:09 GMT, Chad Irby wrote:

In article ,
Buzzer wrote:

"Hamfisted" crew from Ubon in early 1967 blew a pod off a pylon over
North Vietnam.

And a pod fell off a pylon on a plane taking off at Ubon shortly after
that. No cause was found. The "hairy-assed" line mechanics that loaded
the pod that day were never talked to or questioned about it.

If you didn't do it just right, the missile well adapter for ECM pods
wouldn't lock. Once it was pinned in, the thing wasn't going to come
out without some sort of serious failure.

Pods were carried for years hanging from pylons and even the bottom
rack on MERs.
Ever see the two "little" hooks in the pylon that hold bombs and pods
to the pylons?
Take into consideration that bombs and center tanks were dropped to
clean an aircraft up so it could maneuver better. But that pod hung in
there way out from the centerline.

After a couple of problems in Vietnam, they made it impossible for
pilots to jettison ECM pods.

One of the pods that was dumped over the north was one of the
problems. They took the catridges out of the pylons and the latches
were safty wired shortly after that happened.

An apocryphal story they used to tell us was that some fighter jock was
trying to kill a boat on a river. He dropped bombs. Missed. He used
up all of his 20mm. Missed. So he went in on a run and jettisoned the
pod. Hit. one $5,000 boat for a million dollar pod...

I suspect if that happened the pilot bought himself a pod.
Our loss was during Bolo or one of the followups. Crew just got a
little excited and cleaned everything off. Of course if anyone talks
to then Col. Olds they might ask what really happened. I'm sure he
remembers. Just don't ask about the time ECM didn't check to see if
there was a control box in a plane when they loaded the pod.G

In article ,
Buzzer wrote:

Just don't ask about the time ECM didn't check to see if
there was a control box in a plane when they loaded the pod.G

Oh, you can get all sorts of fun stories about loading pods on planes.

We got around a lot of it by running a "full service" pod loading crew.
The same guys put the MWA on, loaded the pod on it, put the control box
in the plane, and ran the tests.

We also had a big advantage for a few years because we were running ECM
from the Component Repair Squadron, so the same guys who fixed the boxes
installed them on the planes.

--
cirby at cfl.rr.com

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

On Fri, 19 Sep 2003 16:39:45 GMT, Buzzer wrote:


"Hamfisted" crew from Ubon in early 1967 blew a pod off a pylon over
North Vietnam.

What you just wrote makes no sense. If the crew was "ham-fisted" then
they over-G'd or "pulled" the pod off. If they "blew" the pod, that
would mean jettisoned by cart-firing. Were they "ham-index-fingered"
in actuating the toggle switch?

Initial installation of the pods at Korat in late Oct. of '66 when
they were highly classified was uncarted, so "blowing" a pod wasn't an
option. And, considering the relatively minimal size and weight,
wouldn't have been worth the time necessary to find the toggle, break
the safety wire, flip the safety cover, establish the necessary
jettison parameters and then "blow."

And a pod fell off a pylon on a plane taking off at Ubon shortly after
that. No cause was found. The "hairy-assed" line mechanics that loaded
the pod that day were never talked to or questioned about it.

If the pod "fell off" then an investigation occurred. The maintenance
supervisor that signed the AFTO-781 on the install was undoubtedly
questioned. Are you speaking of facts or stories you heard?


Pods were carried for years hanging from pylons and even the bottom
rack on MERs.

Pods were carried on the F-4 on inboard pylons and on the F-105 on
outboard pylons. I never saw one carried on a TER or MER. Interposing
a secondary rack, particularly one without aircraft power available
(except for the RAT-driven QRC-160) would be useless.

In '72 and for all the years I carried ALQ-119s in Europe, we carried
ECM pods in a Sparrow well on the F-4.

Ever see the two "little" hooks in the pylon that hold bombs and pods
to the pylons?

Yep, seen a lot of those little hooks. If they could hold an M-118
(3000 pound GP bomb) at 4 G, I've gotta think they could retain an ECM
pod at a lot more G.

Take into consideration that bombs and center tanks were dropped to
clean an aircraft up so it could maneuver better. But that pod hung in
there way out from the centerline.

The C/L tank, particularly on AF F-4s was a poorly engineered piece of
dreck. Bombs were lots of weight and lots of drag. ECM pods, on the
other hand were light, small, low drag and generally uncarted. And, if
you were being attacked by a MiG with radar, AKA MiG-21 or -19, you
might like to be throwing some electrons his way.

You've not made the case.

In article ,
Ed Rasimus wrote:

ECM pods, on the other hand were light, small, low drag and generally
uncarted. And, if you were being attacked by a MiG with radar, AKA
MiG-21 or -19, you might like to be throwing some electrons his way.

You have to rmember that for at least some of the Vietnam War, some
pilots didn't like ECM pods at *all*. Weren't manly enough, or
something. After they started noticing a somewhat higher survival rate
among pilots with pods, they got the message.

But by the early 1980s, a lot of jet jockeys were back to the "pods are
for wimps" sort of attitude. I saw it every time we loaded the 119s
onto F-4s for exercises. And then we had a squadron go to Red Flag, and
suddenly all of the pilots were wanting one every damned day... getting
"shot down" a few times with no recourse tends to do that.

--


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