HUD goes Tango-Uniform. Do you RTB?
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HUD goes Tango-Uniform. Do you RTB?
On another post Beagle mentioned this about a glass cockpit, in the context of a tail chase:
Made me wonder that with all the Gucci (love that word, sorry) helmets and HUD's if you lose the electronics in either would a modern FJ pilot be forced to abort the mission?
In other words have the days of Stop Watches and Charts long gone in modern Fast Jet fleets?
With all that gucci glass, will Bloggs be spending longer time 'head-in' than was accepted in aircraft such as the Bulldog or JP?
In other words have the days of Stop Watches and Charts long gone in modern Fast Jet fleets?
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It depends on what it is you are doing; the phase of the mission and its importance.
Most FJ HUDs are not the primary flight reference so it isn't an essential item. It could just be the projection system and a "HUD" display could be available on head-down display.
There are lots of considerations and eventualities however if you could get the aircraft back on the ground and fixed for the next sortie quickly then it may be the best course of action.
Most FJ HUDs are not the primary flight reference so it isn't an essential item. It could just be the projection system and a "HUD" display could be available on head-down display.
There are lots of considerations and eventualities however if you could get the aircraft back on the ground and fixed for the next sortie quickly then it may be the best course of action.
I don't own this space under my name. I should have leased it while I still could
To add to MSOCS, in WW2, pressing on and unloading your bombs in the target area was seen as essential to the aim. If you and your aircraft perished in the event then there were more to follow you.
Today, if your system is degraded to the extent that you might miss the target then the correct thing to do is RTB. If your weapons are needed for effect, hit or miss, then pressing on might still make sense.
Better by far though not to risk your scarce airframe for a miss.
During one cold war mission we experienced a number of lightning strikes; our option was to clear the area and may be RTB or press on. We pressed on.
Today, if your system is degraded to the extent that you might miss the target then the correct thing to do is RTB. If your weapons are needed for effect, hit or miss, then pressing on might still make sense.
Better by far though not to risk your scarce airframe for a miss.
During one cold war mission we experienced a number of lightning strikes; our option was to clear the area and may be RTB or press on. We pressed on.
In other words have the days of Stop Watches and Charts long gone in modern Fast Jet fleets?
Losing a HUD and HMS would not have any significant effect on the safe operation and navigation of the aircraft - as stated by others, flight safety-critical functions are backed up elsewhere. However it could entirely remove the ability to aim guns or visual air-to-air missile shots and would probably force the pilot to spend an unhealthy amount of time looking at heads-down displays for tactical information. It is this effect on mission capability, rather than any effect on the basic aspects of flying, that would be most likely to handicap an aircraft suffering display failures.
Lightning Battle Flight launched from GUT for live missile firing at Aberporth.
Radar fails en-route, then LFS (poor HUD) fails when on the range.
Chinagraph pencil ‘aiming’ cross placed on centre windscreen; aircraft and missile pointed at the target, acquisition, fire, live warhead success.
Return via Valley with bottle and 200 (always kept under Battle Flight seats) – HM customs notified via ‘Jones the plod’, but the aircraft was always in a restricted area.
Train as you are going to flight – fight as you train.
Radar fails en-route, then LFS (poor HUD) fails when on the range.
Chinagraph pencil ‘aiming’ cross placed on centre windscreen; aircraft and missile pointed at the target, acquisition, fire, live warhead success.
Return via Valley with bottle and 200 (always kept under Battle Flight seats) – HM customs notified via ‘Jones the plod’, but the aircraft was always in a restricted area.
Train as you are going to flight – fight as you train.
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Safetypee,
That get-around clearly worked in its time however - and to use your example - in the age of BVR and HOBS missile profiles it would be a brave and stupid pilot to do such a thing on a training sortie nowadays. Indeed, I'd rip them a new one in the debrief. As I intimated earlier, the context of the mission and its imperative drives the risk you need to take but one must always ask whether it is within one's gift to take it or elevate it in the first place.
That said, thanks for sharing your WIWOL experience!
That get-around clearly worked in its time however - and to use your example - in the age of BVR and HOBS missile profiles it would be a brave and stupid pilot to do such a thing on a training sortie nowadays. Indeed, I'd rip them a new one in the debrief. As I intimated earlier, the context of the mission and its imperative drives the risk you need to take but one must always ask whether it is within one's gift to take it or elevate it in the first place.
That said, thanks for sharing your WIWOL experience!
Originally Posted by MSOCS
Most FJ HUDs are not the primary flight reference
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What would this chap do if he's helmet goes U/S ?
F35 Helmet at RAF Boscombe Down | Latest News from Helmet Integrated Systems Ltd
I suppose he could eject and scare the enemy to death.
F35 Helmet at RAF Boscombe Down | Latest News from Helmet Integrated Systems Ltd
I suppose he could eject and scare the enemy to death.
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CM,
Sorry. My understanding is that certification of a HUD as a PFR, to the demanded SIL, is very rare. HD Insts are more easily PFR compliant as far as standards are concerned for flight critical functions, therefore most FJ have a note in their RtS stating such.
The fact that aircrew spend 99% of their sortie time using the HUD (i.e "primarily" using it) is another matter.
Sorry. My understanding is that certification of a HUD as a PFR, to the demanded SIL, is very rare. HD Insts are more easily PFR compliant as far as standards are concerned for flight critical functions, therefore most FJ have a note in their RtS stating such.
The fact that aircrew spend 99% of their sortie time using the HUD (i.e "primarily" using it) is another matter.
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Lionel, that opens a different can of worms. Flown in the 787 twice, loved it.
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LOM,
I can confirm that. The FA2 HUD was assessed by Boscombe Down to be carrying 'primary flight display information' quite late on in its test programme. First one as far as I am aware, but happy to be corrected.
BD then recommended a (highly expensive) programme of software analysis, which the MoD agreed to fund. After 6 months (having spent most of the dosh) they reported that they couldn't carry out any software analysis.
Great result - not.
Military aircraft cockpit display design (and certification) is one of those somewhat arcane areas where each major country has its own rather firmly held set of standards, opinions (or prejudices - take yer pick), over which fairly endless discussions can be held. In some cases, influential test pilots with strongly held opinions can be, well, influential. Add in the known fact that asking five pilots any question results in at least 6 answers can make delivering an 'acceptable' cockpit a bit of a saga.
As far as I know, HUDs have been classed as primary flight displays for some years now.
Happy New Year to all those sorting out the displays,
Engines
I can confirm that. The FA2 HUD was assessed by Boscombe Down to be carrying 'primary flight display information' quite late on in its test programme. First one as far as I am aware, but happy to be corrected.
BD then recommended a (highly expensive) programme of software analysis, which the MoD agreed to fund. After 6 months (having spent most of the dosh) they reported that they couldn't carry out any software analysis.
Great result - not.
Military aircraft cockpit display design (and certification) is one of those somewhat arcane areas where each major country has its own rather firmly held set of standards, opinions (or prejudices - take yer pick), over which fairly endless discussions can be held. In some cases, influential test pilots with strongly held opinions can be, well, influential. Add in the known fact that asking five pilots any question results in at least 6 answers can make delivering an 'acceptable' cockpit a bit of a saga.
As far as I know, HUDs have been classed as primary flight displays for some years now.
Happy New Year to all those sorting out the displays,
Engines
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The Typhoon HUD is Class 1 software for the majority of the primary flight reference symbology, hence guaranteed integrity, with no need to cross reference.
If the system detects errors (within tolerances) a computer handover occurs, if the errors continue, the symbology will occult, a warning given to the pilot, which then requires the use of other displays. (MHDs or GUHs)
This was the first of its kind (and may still be) and a customer requirement (CM may know more) which was an unknown at the time, however through lots of hard work and testing became a reality.
Unsure if there are any other Class 1 HUD/HMDs now in use.
GTP
If the system detects errors (within tolerances) a computer handover occurs, if the errors continue, the symbology will occult, a warning given to the pilot, which then requires the use of other displays. (MHDs or GUHs)
This was the first of its kind (and may still be) and a customer requirement (CM may know more) which was an unknown at the time, however through lots of hard work and testing became a reality.
Unsure if there are any other Class 1 HUD/HMDs now in use.
GTP
Originally Posted by MSOCS
The fact that aircrew spend 99% of their sortie time using the HUD (i.e "primarily" using it) is another matter.
I don't recall the Tornado HUD (all marks) ever being cleared as the primary flight reference and given where we are with DAL I would be surprised if the RTS changed, even for the GR4.
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Again, more than happy to be educated on this but my understanding is that Typhoon is the only UK FJ with the required assurances that GTPerformer covered very eloquently in his post.
HUD failure robbed me of my fifth kill in'82; both missiles fired (successfully) and only guns remaining. Wasn't good at no-HUD, hi-deflection shot; guess I should have practised more with my 12-bore!
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I vaguely remember something from my IRE ground school that the HUD on the Harrier (GR7/9) couldn't be classified as the PFR as it didn't have an electrical back up. Single engine, single gen if you lost AC power you lost the HUD (same with an MC fail), hence the restriction in the RTS. MSOCS is that correct?
Mogwi - Awesome post!!!
Mogwi - Awesome post!!!