Safe seperation at Mach 2
Thread Starter
Safe seperation at Mach 2
What is a safe minimum distance between aircraft travelling at M2.0?
If one arcraft manoverers around another (for say a phot shoot) is their much turbulence?
Are stick inputs speed sensitive? Is making height adjustments of say 50 feet, difficult at Mach 2?
Mickjoebill
If one arcraft manoverers around another (for say a phot shoot) is their much turbulence?
Are stick inputs speed sensitive? Is making height adjustments of say 50 feet, difficult at Mach 2?
Mickjoebill
Thread Starter
Separation at Mach 2
"Well your never going to get to mach 2 in your Cessna now are you, and in any case learn the differance between their and there before dreaming."
A rude, uninformative answer with as many spelling mistakes as my post!
But do you know the answer to the question?
Dreaming? no, planning.
Some forum!
Mickjoebill
A rude, uninformative answer with as many spelling mistakes as my post!
But do you know the answer to the question?
Dreaming? no, planning.
Some forum!
Mickjoebill
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Go on then...............I know I should'nt.........but planning what
all spelling mistakes are "df" alcohol induced
PS.........I think what spot 4 was trying to say was if you don't know the answer then the chaces are you aint never going to need to know the answer................unless of course you have sh@t loads of wonga and are about to pay for a "real quick" trip............however if this is the case i doubt the instructor will let you "pole" at those speeds as he pobably reads these forums and will already have your number
all spelling mistakes are "df" alcohol induced
PS.........I think what spot 4 was trying to say was if you don't know the answer then the chaces are you aint never going to need to know the answer................unless of course you have sh@t loads of wonga and are about to pay for a "real quick" trip............however if this is the case i doubt the instructor will let you "pole" at those speeds as he pobably reads these forums and will already have your number
Mach number technique for longitudinal aircraft separation is often used by ATC and can be based on time (usually 10 minutes reducing to 5 if the preceding aircraft is M0.06 faster then the following aircraft), or if using RNAV, distance, usually 80NM, but can reduce to 50NM (RNP10) or 30NM with RNP4 + ADS...
I am not an ATC'er, so don't ask me any more...
I am not an ATC'er, so don't ask me any more...
Thread Starter
seperation at Mach2
Thanks! I'm planning a air to air photo shoot using military aircraft. 2000 to 3000 feet seperation is about the (photographic) limit for this particular assignment.
Remaining Mach 2 questions
Safe minimum distance in regard to flying through other aircrafts wake.
Ability to control height within 50-100 feet?
Other factors in loose formation flying at Mach 2?
A reduction in speed to Mach1 make us safer or get us closer?
Anyone flown through a Mach2 wake at close quarters? Common event?
I'm a pro director of photography... wouldn't be much of a pro pilot asking these questions
My ppl? did that for a bet.
Mickjoebill
Remaining Mach 2 questions
Safe minimum distance in regard to flying through other aircrafts wake.
Ability to control height within 50-100 feet?
Other factors in loose formation flying at Mach 2?
A reduction in speed to Mach1 make us safer or get us closer?
Anyone flown through a Mach2 wake at close quarters? Common event?
I'm a pro director of photography... wouldn't be much of a pro pilot asking these questions
My ppl? did that for a bet.
Mickjoebill
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I did a visit to Eastern Radar in the late eighties: An F1-11 doing a `High speed run` up the North Sea got his own individual radar controller and it was all over in a few seconds (East Anglia to Scotland that is). At that speed once you have focused your camera the aircraft will be fuel priority and running for home. I would expect the min separation at that speed to be considerable. Not many mach 2 folks hereabouts, but you may get your answer.
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I may be missing something here but what is the difference in a photo of an aircraft doing Mach 2 and one doing 250 kts? Assuming of course you are not simply filming the Mach meter.
Have you tried talking to the guys who will be actually flying these Mach 2 wonderbirds. What aircraft type is it?
As I said, your "assignment" and the need for speed has lost me a bit!
Have you tried talking to the guys who will be actually flying these Mach 2 wonderbirds. What aircraft type is it?
As I said, your "assignment" and the need for speed has lost me a bit!
2000' up to FL450, 4000' above (not that we have anything that can get above FL450 and not stall-there's a challenge!) and 5nms. Course if we try to get 5 nms then we'll either end up with 50 or a bit of a mess! Happy snapping!
Thread Starter
Safe seperation
So in irregular operations such as a air to air shoot can one get closer than 5 miles?
There are good answers to your queries regarding why at Mach2 (Mach 1 may be workable) and why I'm asking it in a public forum. Politics and time constraits come into it.
Anyone with experience flying close and supersonic? Better still anyone been involved in a supersonic air to air photoshoot?
Putting aviation law aside I'm looking for sound reasons why I can't get 2000 feet from an aircraft at Mach 1 to 2. OK, it is a tall order...but is it possible with saftey?
Understand limited endurance.
Altidude would be above 40000 feet.
Mickjoebill
There are good answers to your queries regarding why at Mach2 (Mach 1 may be workable) and why I'm asking it in a public forum. Politics and time constraits come into it.
Anyone with experience flying close and supersonic? Better still anyone been involved in a supersonic air to air photoshoot?
Putting aviation law aside I'm looking for sound reasons why I can't get 2000 feet from an aircraft at Mach 1 to 2. OK, it is a tall order...but is it possible with saftey?
Understand limited endurance.
Altidude would be above 40000 feet.
Mickjoebill
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MJB - never done formation at Mach 2 (the Lightning did not have enough fuel to get two aircraft close enough for that 
) but I have at M1.3 and we gave it a wide berth just in case. I've experienced M1+ shockwaves and they bounce! I certainly would not go back past about 60 deg swept. It use to be reckoned that a supersonic fighter flying over a heli would remove the rotors! I would think, though, that 2000ft abreast would be ok at say M1.3, but not much fine manouevre left. M1.3 should cope at 40k+ a bit. I seem to remember (long time ago) IAS around 230-240kts at 40k and M1.3??
Hopefully a mil 'up-to-date' will help you, but I'm with Chris Kebab - WHY M2? Who on earth is going to know it wasn't 300kts? Unless of course you are after some sort of shockwave effect and I'm sure you'll be disappointed and out of pocket! If it is the high-altitude you are after, I suggest you use a computer
For info, the shockwave angle sharpens to become more of a cone as M increases, starting at almost 90deg at M1.0, so there should be little interference at a reasonable range, but as for 50-100 ft tweaks - I doubt it! Without going into complex flight 'bits', you have lowish control powers due to lowish IAS but high inertia due to high TAS, eventually getting to M20+ in orbit with ZERO control power!
Try writing to BAE or the Mil research places- they have done similar for supersonic weapons release trials. Whether they will tell you............. Post this whole thread on the Flight Test forum??
On second thoughts - on behalf of the forum mods - please do NOT duplicate this post on FTF. Best to post a brief link to this thread in FTF. If you cannot do that, or want the whole thread moved, let me know by Private Message
) but I have at M1.3 and we gave it a wide berth just in case. I've experienced M1+ shockwaves and they bounce! I certainly would not go back past about 60 deg swept. It use to be reckoned that a supersonic fighter flying over a heli would remove the rotors! I would think, though, that 2000ft abreast would be ok at say M1.3, but not much fine manouevre left. M1.3 should cope at 40k+ a bit. I seem to remember (long time ago) IAS around 230-240kts at 40k and M1.3??Hopefully a mil 'up-to-date' will help you, but I'm with Chris Kebab - WHY M2? Who on earth is going to know it wasn't 300kts? Unless of course you are after some sort of shockwave effect and I'm sure you'll be disappointed and out of pocket! If it is the high-altitude you are after, I suggest you use a computer
For info, the shockwave angle sharpens to become more of a cone as M increases, starting at almost 90deg at M1.0, so there should be little interference at a reasonable range, but as for 50-100 ft tweaks - I doubt it! Without going into complex flight 'bits', you have lowish control powers due to lowish IAS but high inertia due to high TAS, eventually getting to M20+ in orbit with ZERO control power!
Try writing to BAE or the Mil research places- they have done similar for supersonic weapons release trials. Whether they will tell you............. Post this whole thread on the Flight Test forum??
On second thoughts - on behalf of the forum mods - please do NOT duplicate this post on FTF. Best to post a brief link to this thread in FTF. If you cannot do that, or want the whole thread moved, let me know by Private Message
Last edited by BOAC; 19th Nov 2003 at 17:19.
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Just read BOAC's answer, if I'd done it before I'd started writing this I wouldn't have bothered, but might as well leave it now....
I wouldn't worry about the shock waves, they end up behind you, you are on the point !!
As to separation for filming, at high altitude we have bigger separation rools coz the jets don't have as much manoeuvre potential (higher inertia) available and even a slight heading / altitude changes by a fast mover make it hard for the other guy to get out of the way. You end up looking like a startled rabbit but with 40 miles/minute closure head on!
As to formation, a decent flight control system makes allowances for speed/mach and reduces sensitivity as required. Generally the snag is modulating power smoothly. 1% nozzle at 1300kts provides a lot more power differential than at 200kts. I have tried loose formation well supersonic and that isn't too much of a snag. Passing profiles aren't too bad on targets either, the snag is that inertia rools when you start to break away and a flight path change takes a longer than normal. Most AD pilots have seen the bottom of another aircraft getting rapidly closer as the other guy begins his break away.
Hope that helps a bit,
Ghost
I wouldn't worry about the shock waves, they end up behind you, you are on the point !!
As to separation for filming, at high altitude we have bigger separation rools coz the jets don't have as much manoeuvre potential (higher inertia) available and even a slight heading / altitude changes by a fast mover make it hard for the other guy to get out of the way. You end up looking like a startled rabbit but with 40 miles/minute closure head on!
As to formation, a decent flight control system makes allowances for speed/mach and reduces sensitivity as required. Generally the snag is modulating power smoothly. 1% nozzle at 1300kts provides a lot more power differential than at 200kts. I have tried loose formation well supersonic and that isn't too much of a snag. Passing profiles aren't too bad on targets either, the snag is that inertia rools when you start to break away and a flight path change takes a longer than normal. Most AD pilots have seen the bottom of another aircraft getting rapidly closer as the other guy begins his break away.
Hope that helps a bit,
Ghost
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M2.0 formation photo shoot is pretty unlikey now unless you can hire a couple of concordes. Recently did a loose formation M2.0 run about 1nm sep. Photo wouldnt look that different to a much slower speed though since we were up above 40k. Contrails looked very cool though.
Would be better getting some sort of low level M1+ run I would think. Get a sense of speed from the ground rush.
Formation supersonic is not a problem. Initial buffet going trans sonic but as long as you have power available to modulate and hold position you could almost be going any speed.
Its not a magic barrier! Thought that myth vanished when Chuck Yeager did his stuff.
If you are running 2 fast jets for the shoot then all this talk of minimum seperation does not apply. Get in close on the wing, hang out loose (couple of hundred feet) or go out to a mile or two. You drive the shoot, pilots drive the platforms to get the shots. We dont mind doing it either as long as we get a copy.
Wouldnt recommend flying thru jet wash as a habit anyway but most probably you will feel loads of turbulence, you may get uncommanded roll, pitch or yaw moments, worst case flame out an engine! As for how close you could get, check out the reds and that might answer your question.
Lots of hilarious (not) answers to a genuine question in the last few posts. I thought people on this forum might have been a bit more welcoming to someone who may never get thru the mach. Bit like a harrier mate huh
Best of luck with the shoot
Would be better getting some sort of low level M1+ run I would think. Get a sense of speed from the ground rush.
Formation supersonic is not a problem. Initial buffet going trans sonic but as long as you have power available to modulate and hold position you could almost be going any speed.
Its not a magic barrier! Thought that myth vanished when Chuck Yeager did his stuff.
If you are running 2 fast jets for the shoot then all this talk of minimum seperation does not apply. Get in close on the wing, hang out loose (couple of hundred feet) or go out to a mile or two. You drive the shoot, pilots drive the platforms to get the shots. We dont mind doing it either as long as we get a copy.
Wouldnt recommend flying thru jet wash as a habit anyway but most probably you will feel loads of turbulence, you may get uncommanded roll, pitch or yaw moments, worst case flame out an engine! As for how close you could get, check out the reds and that might answer your question.
Lots of hilarious (not) answers to a genuine question in the last few posts. I thought people on this forum might have been a bit more welcoming to someone who may never get thru the mach. Bit like a harrier mate huh
Best of luck with the shoot
Thread Starter
"I wouldn't worry about the shock waves, they end up behind you, you are on the point !!"
Thanks Ghost Flyer,
I was wondering about turbulence if we slowly manouvered into the other guys shock wave.
Since the camera wil be hand held could one expect severe turbulence that would turn the backseat into a blender? Camera weight would be in the range of 4 to 8 kilos.
"As to formation, a decent flight control system makes allowances for speed/mach and reduces sensitivity as required. Generally the snag is modulating power smoothly. 1% nozzle at 1300kts provides a lot more power differential than at 200kts."
So is it a fiddle to match speed of the aircraft we are shooting? Camera ship is different aircraft type to subject aircraft. Subject aircraft is mostly sticking to a flight plan.
"I have tried loose formation well supersonic and that isn't too much of a snag."
Good to hear. How loose? less than 2000 feet?
"the snag is that inertia rools when you start to break away and a flight path change takes a longer than normal. Most AD pilots have seen the bottom of another aircraft getting rapidly closer as the other guy begins his break away."
Ok. Dynamic breakaways will be at the bottom of the wish list.
"Hope that helps a bit"
Very constructive thank you.
Mickjoebill
Thanks Ghost Flyer,
I was wondering about turbulence if we slowly manouvered into the other guys shock wave.
Since the camera wil be hand held could one expect severe turbulence that would turn the backseat into a blender? Camera weight would be in the range of 4 to 8 kilos.
"As to formation, a decent flight control system makes allowances for speed/mach and reduces sensitivity as required. Generally the snag is modulating power smoothly. 1% nozzle at 1300kts provides a lot more power differential than at 200kts."
So is it a fiddle to match speed of the aircraft we are shooting? Camera ship is different aircraft type to subject aircraft. Subject aircraft is mostly sticking to a flight plan.
"I have tried loose formation well supersonic and that isn't too much of a snag."
Good to hear. How loose? less than 2000 feet?
"the snag is that inertia rools when you start to break away and a flight path change takes a longer than normal. Most AD pilots have seen the bottom of another aircraft getting rapidly closer as the other guy begins his break away."
Ok. Dynamic breakaways will be at the bottom of the wish list.
"Hope that helps a bit"
Very constructive thank you.
Mickjoebill
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mickjoebill - after 'last chance' air to airs of Concorde doing her stuff over the Bay of Biscay next Wednesday are we? Which French fighter jock have you bribed to do the intercept? 
You do have to wonder why someone with the "clout" to get a photo shoot of 2 dis-similar types in formation at M2+ at 40K+ is asking how to do it on this forum !!
If it's for real why not give more details?
If it's for real why not ask the pilots that are going to be doing it?
If it's for real then the group staffs (or their equivalent) will give guidance - probably using advice from ETPS/OEU or equivalent.
I have to side with the first reply to this thread. If we want to have a discussion about formation at high mach, fine. What we don't need is someone with a camera bag, scanner and Iron Maiden t-shirt using this forum as a break from dungeons and dragons.
Edited for tooping
If it's for real why not give more details?
If it's for real why not ask the pilots that are going to be doing it?
If it's for real then the group staffs (or their equivalent) will give guidance - probably using advice from ETPS/OEU or equivalent.
I have to side with the first reply to this thread. If we want to have a discussion about formation at high mach, fine. What we don't need is someone with a camera bag, scanner and Iron Maiden t-shirt using this forum as a break from dungeons and dragons.
Edited for tooping
Last edited by Flap62; 20th Nov 2003 at 18:23.