Bombed my plane

[BigHairyGobbler]

I made a training mission in DCS Stable 2.5.5 and my F-16c on the Persian Gulf map. The target was a convoy of trucks and I was coming in to bomb them using CCIP with six pulses of mk82 pairs (12 bombs total). NT fusing and 85 foot spacing. I had a targeting pod and single external fuel tank on centerline. I was flying level wings with shallow dive when I released bombs at 4000 ft I blew up. I replayed the track and upon pickle, the bombs all rattled on the wings with some releasing and about half blowing up on my pylons.

 

Is this a bug or something maybe I did wrong. I was in cat iii mode as well. Thanks.

[Snacko]

Were you pushing down on your stick a little bit, and crashed into your bombs as they left the rails?

[silverdevil]

i did this before with hornet. my track looked like bomb dropped a bit but raised upwards into the plane. i thought perhaps turbulence. or bomb initially was speed of AC but lost velocity and AC caught up to it.

[BigHairyGobbler]

Were you pushing down on your stick a little bit, and crashed into your bombs as they left the rails?

 

I was in a shallow dive but have CCIP bombed using this method dozens of times without blowing myself up. I think I was flying around 430 knots.

 

Edit: Just reflew mission without bombing myself so maybe a SNAFU in the game.

Edited April 16, 2020 by BigHairyGobbler

[razo+r]

It doesn't matter if you were in a dive or not, if you Push your stick, you will fly into your own bombs most likely. Were you pushing your stick?

[BigHairyGobbler]

Hard to tell if I was pushing stick forward. I was in shallow dive and on target so I doubt it

[Dusty44]

Happens to the best, even on gun runs!

 

https://www.popularmechanics.com/military/aviation/a27078461/dutch-f-16-flew-into-its-own-gunfire/

[Notso]

I made a training mission in DCS Stable 2.5.5 and my F-16c on the Persian Gulf map. The target was a convoy of trucks and I was coming in to bomb them using CCIP with six pulses of mk82 pairs (12 bombs total). NT fusing and 85 foot spacing. I had a targeting pod and single external fuel tank on centerline. I was flying level wings with shallow dive when I released bombs at 4000 ft I blew up. I replayed the track and upon pickle, the bombs all rattled on the wings with some releasing and about half blowing up on my pylons.

 

Is this a bug or something maybe I did wrong. I was in cat iii mode as well. Thanks.

 

Sounds like you had some negative G on the jet. If you have the ability, go back and look at your track replay and see what your G meter in the HUD was reading at pickle.

[Stubbies2003]

Happens to the best, even on gun runs!

 

https://www.popularmechanics.com/military/aviation/a27078461/dutch-f-16-flew-into-its-own-gunfire/

 

 

That is a different story all together and I remember doing the math on this one. Esp on a strafing run where you are already close to the ground there isn't enough time and space to catch up to your own shots. They added at the bottom what the most likely culprit was. Pilot error in NOT getting into the ricochet zone and it was ricochets that hit the aircraft not him flying into the bullets he shot.

[BigHairyGobbler]

Sounds like you had some negative G on the jet. If you have the ability, go back and look at your track replay and see what your G meter in the HUD was reading at pickle.

 

I didn't save the track but will keep an eye on negative-g's.

[Dusty44]

That is a different story all together and I remember doing the math on this one. Esp on a strafing run where you are already close to the ground there isn't enough time and space to catch up to your own shots. They added at the bottom what the most likely culprit was. Pilot error in NOT getting into the ricochet zone and it was ricochets that hit the aircraft not him flying into the bullets he shot.

 

Did you read the entire article including the 1956 incident? The board of inquiry found he flew into his 20mm rounds. But if you did the math then ok.

[mkiii]

How Hard would you have to push the stick to fly into your bombs?

 

Does the F-16 only have gravity release then? I assumed that bombs were pushed off by gun & bolt ejection mechanisms, and that was quite a punch, especially with gravity helping.

[EDIT]

Not very hard it seems. I just dropped a stick of Practice bombs straight up through my wings ;)

Edited April 18, 2020 by mkiii

[sobek]

How Hard would you have to push the stick to fly into your bombs?

 

 

The bombs follow a ballistic path, so 0g. If you fly with less than 0g, your path will quickly intersect the bomb path.

[mkiii]

Yes, true, but they do also tend to go in a downwards direction of their own accord hopefully. ;) To be honest - due to a sense of virtual self preservation, It's not something I ever did before - I do get that a released bomb is on the same general trajectory as me when I release it - so rule 1 is go where the bomb isn't - unless it is a special weapon that requires level flight.

 

Either way, I did find it amusingly simple to make practice bombs hurtle upwards through my wings, with no damage to wing nor bomb, after a slight push on the stick. Having always assumed that the ejector was there to make sure that a twitchy pilot stayed separate from the bangy thing. Hence my question.

[sobek]

Yes, true, but they do also tend to go in a downwards direction of their own accord hopefully. ;)

 

 

Zero g results in a parabula towards earth. Straight and level is 1g.

[Notso]

How Hard would you have to push the stick to fly into your bombs?

 

Does the F-16 only have gravity release then? I assumed that bombs were pushed off by gun & bolt ejection mechanisms, and that was quite a punch, especially with gravity helping.

[EDIT]

Not very hard it seems. I just dropped a stick of Practice bombs straight up through my wings ;)

 

Yes, the bomb racks will have ejector cartridges similar to a shotgun shell that is supposed to push the bomb (or tank) down and away from the jet to achieve safe separation. But they are limited in how much they can do. Remember, you're talking about a small little push on a 2000lb hunk of iron. It's really not more than a nudge down rather than a violent push. Watch some videos of Edwards or China lake flight test weapons testing and you'll see that it's not a huge push away.

 

To hit the bombs in flight, you would have to be likely less than 0 g, as in negative G. A bombing technique to achieve good accuracy on a dive bomb CCIP attack would be to gently be pushing the stick at release to ensure that you are stable at 1G or slightly less. 0.5-1.0g would be ideal. More than that and you risk not achieving safe separation.

 

Go back and look at your HUD G meter when you pickled to see what it was when the bombs hit you. I'm betting it was something less than 0g.

[Notso]

Zero g results in a parabula towards earth. Straight and level is 1g.

 

Straight line, yes. But not necessarily level. But you can be at 1G in a 45 deg dive as long as you're going in a straight non-curving path.

[Deano87]

Straight line, yes. But not necessarily level. But you can be at 1G in a 45 deg dive as long as you're going in a straight non-curving path.

 

It depends what reference frame you're talking about. If you're viewing it from the reference frame of the aircraft (and by extension the pilot and the G-meter) then I'm not sure thats quite correct.

 

If you're in a consistent 45 degree dive with no pitch rate then the vertical axis of the aircraft is not experiencing 1G, as part of gravity's force is in the longitudinal axis of the aircraft, helping it accelerate.

 

To achieve a load factor of 1G in a 45 degree dive you need to have positive pitch rate, so it cannot be a "straight non-curving path".

 

This is why aircraft that have FBW systems that attempt to hold 1G will tend to pitch up gently while in a dive.

 

To achieve 1G of vertical loading from the aircraft/pilots point of view with no pitch rate you have to be in straight and level flight. Of course you can achieve 1G in other situations, but all of those cases require pitch rate of some kind.

 

 

Aaaand everybody reading is like:

 

:thumbup:

[mkiii]

I have seen some interesting archive footage of stores (prototype testing mainly I think), doing exactly what they are not supposed to do, & either flying upwards or not separating cleanly & taking out the tailplane in the case of a droptank, as they gently rotated rearwards - and upwards. I don't think any of those were due to negative G, just poor designs or configurations.

 

 

Anyhoo - I'm not totally convinced the weapon drop is 100% accurate yet, poor flying aside, and I know for sure that the F16 damage model (at that time at least) was pretty, let us say, basic. At least as wing collision is concerned - there appears to be none. I don't doubt that it will be good in due course. :)

[WildBillKelsoe]

A well versed and popular friend of mine who's ex A-10 pilot told me the way they do CCIP is to trim nose down w little bit before roll in and roll out with flight path marker glued to a known reference ahead of target. That way the problems of inaccuracy are limited to bank and speed.

[Stubbies2003]

Did you read the entire article including the 1956 incident? The board of inquiry found he flew into his 20mm rounds. But if you did the math then ok.

 

 

Yeah at the speed they leave the aircraft at you would have to get WAY too close to the ground on a strafing run to catch up to and run into your own bullets. Only way this can happen without ricochet now is in air to air gun work. Then yes this is a distinct possibility.

 

Basically what you are seeing here is someone the brass likes/good pilot that they do not want to put a bad mark onto his record. Have seen other ridiculous scenarios laid out to cover a pilots read end whom they don't want to lose.

[Cupra]

Isn´t there normally an arming delay of a few seconds.. exploding bombs just moments after release have 2 Options:

- bomb malfunction

- too less arming delay

 

They may hit the plane, but they should not explode. There are some videos around that show what can go wrong at release, but o one of them shows exploding bombs..

[Notso]

Isn´t there normally an arming delay of a few seconds.. exploding bombs just moments after release have 2 Options:

- bomb malfunction

- too less arming delay

 

They may hit the plane, but they should not explode. There are some videos around that show what can go wrong at release, but o one of them shows exploding bombs..

 

Yes, most or all modern fuzes have an arm time delay for just this reason - either to prevent detonation with the aircraft or weapon to weapon impacts too near the jet. Usually a few seconds is more than enough time for the bomb to get far enough away from the jet before it arms to give the jet safe separation time in the unlikely event it armed and immediately went "boom". Unfortunately those features and release procedures are all written in blood.

[Luzifer]

If you're in a consistent 45 degree dive with no pitch rate then the vertical axis of the aircraft is not experiencing 1G, as part of gravity's force is in the longitudinal axis of the aircraft, helping it accelerate.

 

To achieve a load factor of 1G in a 45 degree dive you need to have positive pitch rate, so it cannot be a "straight non-curving path".

 

This isn't right. Earth's gravity will exert 1g vertically, and to experience something different you have to accelerate vertically. Conversely, if your vertical speed is constant (i.e. without acceleration) you will experience 1g.

 

Of course at larger scales you will have to take into account that the gravity field is sort of spherical and a straight horizontal motion has a vertical component relative to earth, but that is orbital mechanics and not really relevant where aircraft are concerned.

 

This is why aircraft that have FBW systems that attempt to hold 1G will tend to pitch up gently while in a dive.

 

They will if you're accelerating in the dive. If your (true) speed increases while in a constant 45° dive that implies your vertical speed is also increasing. A dive at constant speed would be 1g.

[Deano87]

This isn't right. Earth's gravity will exert 1g vertically, and to experience something different you have to accelerate vertically. Conversely, if your vertical speed is constant (i.e. without acceleration) you will experience 1g.

 

You missed the part where I specifically mentioned that the reference frame was the aircraft. In the vertical axis of aircraft (lift vector) then if in a constant 45 degree dive the air frame will not be experiencing 1G of lift loads. The pilot will be experiencing 1G of total gravity yes, but part of that will be towards his seat base, and part of it will be forwards towards the instrument panel. The G meter, which ONLY reads the component that is pushing the pilot into his seat will not read 1G. If you're in a steady state vertical dive, the aircraft has 0G lift loads, the G-meter will read 0 and the pilot will be hanging in his straps towards the instrument panel, presuming that you aren't accelerating.

 

They will if you're accelerating in the dive. If your (true) speed increases while in a constant 45° dive that implies your vertical speed is also increasing. A dive at constant speed would be 1g.

 

No. In an aircraft with an FCS that tries to maintain 1G of lift loading on the aircraft it doesn't care about the portion of the G experienced by the pilot in a 45 degree dive that is pushing him towards the instrument panel and will command a pitch rate to attain 1G of lift loading on the aircraft.

Please I suggest you go and try these 3 tests in either the F-18 or F-16 in the sim.

 

 

Fly low level at max speed. Pull to 45 degrees nose up, note the small forward pressure required to hold 45 degree climb, not the G meter reading (less than 1G) Now release the stick, note how the aircraft starts pitching up to attain 1G of lift loading on the aircraft, the aircraft will continue to pitch all the way up through the vertical until its inverted if not prevented.

 

Now fly a 45 degree dive, notice the forward pressure required to hold 45 degrees, note the G meter reading (less then 1G) Now release the stick, notice the pitch rate the FCS will command to return to 1G of lift loading.

 

Now fly a vertical dive. Noticed the G meter reading of 0, release the stick, noticed the pitch rate the FCS will command to attain 1G.

 

Note that all of the above will hold true regardless of if you are accelerating or decelerating as long as you don't end up too slow and entering the Pitch Rate/AoA FCS regimes found on both aircraft.

 

 

A "straight non-curving path" 45 degree dive, will not place 1G of lift loads on the aircraft, and will not place 1G of separation force on the bombs, which is what this thread was all about.

Edited May 2, 2020 by Deano87