REHEAT ON A TRAINER
The Jaguar was going to be our advanced FJ trainer. It seemed to need it.
EDIT: sorry, slow connection and missed the previous post.
EDIT: sorry, slow connection and missed the previous post.
Last edited by Courtney Mil; 8th Jul 2012 at 20:59.
Join Date: Feb 2006
Location: Hanging off the end of a thread
Posts: 33,068
Received 2,938 Likes
on
1,252 Posts
The Jaguar shown there was originally developed as a trainer, had dual reheat, but required the curvature of the earth to get airborne.
Et Tu Brutus
Et Tu Brutus
Last edited by NutLoose; 8th Jul 2012 at 21:01.
Join Date: Feb 2006
Location: Hanging off the end of a thread
Posts: 33,068
Received 2,938 Likes
on
1,252 Posts
Genstabler, I was on a couple of Jag Sqns as an Engineer and watching one depart Lossie with several 1000 pounders on was embarrassing, the Vulcan was there and rotated in about what seemed like 10 lengths, the Jag appeared to be using Barnes Wallaces bouncing bomb skipping technique out over the sea to become airborne having dissapeared nearly over the horizon.
Join Date: Apr 2008
Location: The Whyte House
Age: 95
Posts: 1,966
Likes: 0
Received 0 Likes
on
0 Posts
I have no idea how much of USAFs syllabus is supersonic these days, or indeed any other day, but the T-38 has been afterburner 'capable' since its introduction into service in 1961.
I suspect that it is rarely used, and of course the T-X program will likely put an end to the widespread employ of afterburner in Western training syllabi.
I suspect that it is rarely used, and of course the T-X program will likely put an end to the widespread employ of afterburner in Western training syllabi.
Last edited by Willard Whyte; 8th Jul 2012 at 21:46.
Slightly disingenuous; the 1980 F16A was a lightweight day (dog)fighter optimised for work at 30k+ 1/2 a gen later than the mud moving Jaguar. A lot of work and treasure went into expanding the capability of F16 to its' current level. Don't think Jaguar ever had more than a belated avionics and engine upgrade.
Still, I think Jaguar was involved in more combat than Tor F3, so it can't have been a total pile of poo?
Still, I think Jaguar was involved in more combat than Tor F3, so it can't have been a total pile of poo?
Join Date: Feb 2006
Location: Hanging off the end of a thread
Posts: 33,068
Received 2,938 Likes
on
1,252 Posts
I have to admit it was a sad day when they went, as said it was a cheap and viable platform, when you used to look at the support the likes of the Tornado or Phantom needed away from base and that of the Jag, the Jag won hands down. Coupled with once the design authority I believe was taken in house the costs dropped even more.
Join Date: Jan 2012
Location: .
Posts: 2,173
Likes: 0
Received 0 Likes
on
0 Posts
So once you got it airborne, how god was the Jag at what it did? The books are full of such comments as it being the "best integrated" of the RAFs attack fleet, but was it really? Is that just rubbish spouted by the unknowing?
Did the French ones - which had simpler systems and I'm guessing were lighter - have better takeoff performance?
Did the French ones - which had simpler systems and I'm guessing were lighter - have better takeoff performance?
The advantages and disadvantages of reheat are much the same on a trainer as on any other aircraft, so here goes:
Advantage
Allows the aircraft to use a smaller engine than required for the specified takeoff performance; the reheat provides the extra thrust required during takeoff. Once airborne, the engine(s) can be run near to its design RPM (usually at the top end of the range) for most of the flight without flying excessively fast and wasting energy through drag. Smaller engines also generally mean smaller aircraft and less drag again. This means that overall fuel efficiency is increased - you just need to save more fuel during the sortie than the reheat burned during takeoff.
Disadvantages
Mechanical complexity (nozzle area control, burner ring, light-up system, fuel injection + pumping)
Fire hazard
IR signature
Noise
Combat manoeuvring generally requires reheat (=lots of fuel)
Potential to run out of fuel very quickly if mishandled
For a training type, the mechanical complexity and the ability for a student to run the fuel out in less than 5 minutes both militate against the incorporation of reheat as a desirable feature! Besides, most training sorties would not benefit from the kind of takeoff vs cruise fuel consumption compromise that the advantages stem from.
Advantage
Allows the aircraft to use a smaller engine than required for the specified takeoff performance; the reheat provides the extra thrust required during takeoff. Once airborne, the engine(s) can be run near to its design RPM (usually at the top end of the range) for most of the flight without flying excessively fast and wasting energy through drag. Smaller engines also generally mean smaller aircraft and less drag again. This means that overall fuel efficiency is increased - you just need to save more fuel during the sortie than the reheat burned during takeoff.
Disadvantages
Mechanical complexity (nozzle area control, burner ring, light-up system, fuel injection + pumping)
Fire hazard
IR signature
Noise
Combat manoeuvring generally requires reheat (=lots of fuel)
Potential to run out of fuel very quickly if mishandled
For a training type, the mechanical complexity and the ability for a student to run the fuel out in less than 5 minutes both militate against the incorporation of reheat as a desirable feature! Besides, most training sorties would not benefit from the kind of takeoff vs cruise fuel consumption compromise that the advantages stem from.
Last edited by Easy Street; 8th Jul 2012 at 22:24.
Avoid imitations
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,576
Received 426 Likes
on
225 Posts
Mock away fellahs, but it was cheap as chips and very effective once it got up.
T-38 uses AB on every take-off and rarely in flight, maybe to get some energy on form rejoins or a loop. Supersonic is a one flight deal, unless you goof and let it point downhill too long on a solo flight.
GF
GF
Advantage
Allows the aircraft to use a smaller engine
than required for the specified takeoff performance
Replace with 'makes a loud band frightening the sh1t out of ground troops'.
'So once you got it airborne, how god was the Jag at what it did? The books are full of such comments as it being the "best integrated" of the RAFs attack fleet, but was it really? Is that just rubbish spouted by the unknowing?'
Answer YES. Trouble with Jaguar was that it was eventually re-designed as a trainer lead-in for TSR2. It needed top speed and the ability to fly LL at M1.2. It could not do that with big wings. So it suffered enormously from lift dependant drag and was hopeless at low speed. But it could do 800 mph at LL (clean). That can't be bad. On my first Maple Flag, no one could catch us. We even had to slow down to drop bombs as they were limited to M 0.95 for release.
Answer YES. Trouble with Jaguar was that it was eventually re-designed as a trainer lead-in for TSR2. It needed top speed and the ability to fly LL at M1.2. It could not do that with big wings. So it suffered enormously from lift dependant drag and was hopeless at low speed. But it could do 800 mph at LL (clean). That can't be bad. On my first Maple Flag, no one could catch us. We even had to slow down to drop bombs as they were limited to M 0.95 for release.
On my first Maple Flag, no one could catch us. We even
had to slow down to drop bombs as they were limited to M 0.95 for
release.
I hope you didn't have drop tanks fitted then - they were limited to 0.9 if memory serves.
....and I well remember outrunning an "Aggressor" F4 on Red Flag.
