F35 v Harrier
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Thank you so much for an interesting discussion. My question was of course simplistic. I was watching vid of f35 landing on down thrust and wondered how it compared to Shar in combat role. I wondered if the f35 was a bit more profligate in fuel. Of course they have, probably, different purposes but the Harrier is still, I believe, used by USM.
I don't own this space under my name. I should have leased it while I still could
Effortless, there you go, after all the discussion about the Harrier bomb truck you changed the aircraft!
Last edited by Pontius Navigator; 5th Oct 2018 at 13:16.
1. Jack the aircraft.
2. Retract the u/c.
3. Lower it onto cradles.
4. Remove the wing (Yes, remove the wing!).
5. Crane the engine out from the top of the fuselage.
6. Crane in the new engine.
7. Replace the wing.
8. Jack the aircraft.
9. Lower the gear.
10. Lower the aircraft onto its wheels.
All this in a heavy sea with no rum ration! Hopefully the Dave will be a bit more user friendly.
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Lechon and others,
It might help if I follow up Mogwi's post with some information about supporting Harriers.
Bluntly, the aircraft was bad (and expensive) to maintain. The Harrier I was a direct development of the prototype P1127, and the amazingly complicated wing lift method to change an engine would normally have been rejected at the design review stage. The Harrier II introduced some limited improvements, but most of the access to items was really, really poor. To Mogwi's list, I would add that removing and replacing the engine meant disturbing, reconnecting and then testing the flying controls, fuel systems, landing gear systems, reaction control hot air ducts and the weapon systems connections to the wing pylons. I would also add that every time you lifted the engine, there was a TON of rectification work required to repair the interior of the fuselage where the mighty Pegasus had simply shaken bits of it loose.
Many parts of the aircraft were fully obsolete and getting replacements was becoming a real challenge. As an example, the undercarriage selection switch was the same item used in the Hawker Sea Fury. (I am not making this up). It was a huge lump of Bakelite and came fitted with rubber insulated wires, which we then had to cut off and replace before installing it. Many other components in the aircraft were antique, unreliable and amazingly hard to get at. The rear end of the aircraft was essentially under engineered, and the tailplane would regularly wear out its bearings. The reaction controls at the rear of the fuselage would shake themselves apart (I mean here in less than 50 hours). The RAF's Harrier fleet would have required a full rear fuselage replacement programme had they gone on in service much longer. The Pegasus engine was not especially reliable, and rarely (if ever) achieved its published life before having to be removed for repair.
But, I loved being associated with the Sea Harrier and the Harrier GR7s. The Harrier's STOVL concept was a work of pure British genius, and gave the UK an aircraft that was the key to winning a vital war in 1982. In the 90s, the Sea Harrier FA2 was one of NATO's most capable air to air combat aircraft. The people were great, the jobs incredibly satisfying, and standing on a deck next to an aircraft that had stopped dead in the sky always gave me a rush. But, time moves on, aircraft have their day, and then they don't. The new replaces the old, as it should, and the F-35B now has to be made to work in service. I know that the RN and RAF personnel charged to do that will succeed, along with their excellent USMC counterparts. Certainly, in combat, the F-35 will be a far more capable machine than the Harrier ever could have been. In support, it will be a challenge. Having worked with the people who took great pains to make servicing it as easy as it can be on an LO aircraft, I also know that it will be a better aircraft to maintain and support at sea. On that, I have no doubts at all.
Best Regards as ever to all those who are going to make the aircraft a success,
Engines
It might help if I follow up Mogwi's post with some information about supporting Harriers.
Bluntly, the aircraft was bad (and expensive) to maintain. The Harrier I was a direct development of the prototype P1127, and the amazingly complicated wing lift method to change an engine would normally have been rejected at the design review stage. The Harrier II introduced some limited improvements, but most of the access to items was really, really poor. To Mogwi's list, I would add that removing and replacing the engine meant disturbing, reconnecting and then testing the flying controls, fuel systems, landing gear systems, reaction control hot air ducts and the weapon systems connections to the wing pylons. I would also add that every time you lifted the engine, there was a TON of rectification work required to repair the interior of the fuselage where the mighty Pegasus had simply shaken bits of it loose.
Many parts of the aircraft were fully obsolete and getting replacements was becoming a real challenge. As an example, the undercarriage selection switch was the same item used in the Hawker Sea Fury. (I am not making this up). It was a huge lump of Bakelite and came fitted with rubber insulated wires, which we then had to cut off and replace before installing it. Many other components in the aircraft were antique, unreliable and amazingly hard to get at. The rear end of the aircraft was essentially under engineered, and the tailplane would regularly wear out its bearings. The reaction controls at the rear of the fuselage would shake themselves apart (I mean here in less than 50 hours). The RAF's Harrier fleet would have required a full rear fuselage replacement programme had they gone on in service much longer. The Pegasus engine was not especially reliable, and rarely (if ever) achieved its published life before having to be removed for repair.
But, I loved being associated with the Sea Harrier and the Harrier GR7s. The Harrier's STOVL concept was a work of pure British genius, and gave the UK an aircraft that was the key to winning a vital war in 1982. In the 90s, the Sea Harrier FA2 was one of NATO's most capable air to air combat aircraft. The people were great, the jobs incredibly satisfying, and standing on a deck next to an aircraft that had stopped dead in the sky always gave me a rush. But, time moves on, aircraft have their day, and then they don't. The new replaces the old, as it should, and the F-35B now has to be made to work in service. I know that the RN and RAF personnel charged to do that will succeed, along with their excellent USMC counterparts. Certainly, in combat, the F-35 will be a far more capable machine than the Harrier ever could have been. In support, it will be a challenge. Having worked with the people who took great pains to make servicing it as easy as it can be on an LO aircraft, I also know that it will be a better aircraft to maintain and support at sea. On that, I have no doubts at all.
Best Regards as ever to all those who are going to make the aircraft a success,
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The simple question of this thread has led to the sharing of very interesting experiences. It got me stooging around and I found some interesting stats here on F-35: -
F-35 LIGHTNING II PROGRAM STATUS AND FAST FACTS
October 4, 2018
https://www.f35.com/assets/uploads/d...Facts10-18.pdf
I know it wasnt the question but looking at quoted figures for combat radius shows the F-35 comfortably ahead. Although not any detail of profile or configuration, it is such a large margin that is probably indicative of the F-35 being much better; I am assuming also that the GR7 Wiki range is for internal fuel only.
Endurance will also be significantly affected by the airframe. I am guessing again that the speed for maximum endurance is subsonic (no transonic flow). From what still rattles around my brain, wing lift will be one of the largest components of drag and that will depend significantly on the aspect ratio (AR); higher AR usually means lower lift induced drag (if memory ok). I also compared wing loading and thrust/weight; figures shown below (Harrier from wiki).
I was surprised to see that the Harrier has such good figures wrt F-35B. AR and wing loading are similar or better. I was stunned to see the Harrier thrust/weight; it trounces the F-35, except the lighter F-35B in full afterburner.
I know there is more to it, but as a rough stab at comparisons the Harrier airframe looks like it could hold its own with an F-35 airframe. I am guessing the reason for the GR7 having a much smaller combat range (assuming all else equal; big 'if') is because although it probably has a more efficient engine (turbofan) the extra drag from the large frontal area offsets the advantages of the engine efficiency.
But if these two aircraft went nose to nose with each other, the respectable relative wing loading and the much higher T/W of the Harrier would likely give it the advantage. I remember reading of how the Sea Harrier FRS1 gobbled F-15's once within Sidewinder range; did the FA2 do even better with Blue Vixen/AMRAAM in the package?
Although Stealth of the F-35 gives it a huge advantage in todays arena of long range radar and weapons, but that stealth could well disappear in the future. Advances such as quantum radar could well negate the stealth of the F-35, especially if one is made small enough to fit in the nose of a Harrier.
It may sound far fetched but a senior admiral of the USN a few years ago expressed concern that we are putting all our eggs in one basket regarding stealth. His view was that at some point technology will nullify stealthy designs.
Would that lead to a new lease of life for aircraft like the Harrier? A fraction of the cost of an F-35 but highly effective aircraft in that scenario. In reality the combat scenario will not stand still. When stealth is finally negated, probably there will be no manned combat aircraft and laser weapons will be used to shoot down aircraft.
But these stats show just what an effective aircraft the Harrier was. I doubt we have got as much value for money in any other fighter except the Spitfire and Hurricane.
F-35 LIGHTNING II PROGRAM STATUS AND FAST FACTS
October 4, 2018
https://www.f35.com/assets/uploads/d...Facts10-18.pdf
I know it wasnt the question but looking at quoted figures for combat radius shows the F-35 comfortably ahead. Although not any detail of profile or configuration, it is such a large margin that is probably indicative of the F-35 being much better; I am assuming also that the GR7 Wiki range is for internal fuel only.
Endurance will also be significantly affected by the airframe. I am guessing again that the speed for maximum endurance is subsonic (no transonic flow). From what still rattles around my brain, wing lift will be one of the largest components of drag and that will depend significantly on the aspect ratio (AR); higher AR usually means lower lift induced drag (if memory ok). I also compared wing loading and thrust/weight; figures shown below (Harrier from wiki).
I was surprised to see that the Harrier has such good figures wrt F-35B. AR and wing loading are similar or better. I was stunned to see the Harrier thrust/weight; it trounces the F-35, except the lighter F-35B in full afterburner.
I know there is more to it, but as a rough stab at comparisons the Harrier airframe looks like it could hold its own with an F-35 airframe. I am guessing the reason for the GR7 having a much smaller combat range (assuming all else equal; big 'if') is because although it probably has a more efficient engine (turbofan) the extra drag from the large frontal area offsets the advantages of the engine efficiency.
But if these two aircraft went nose to nose with each other, the respectable relative wing loading and the much higher T/W of the Harrier would likely give it the advantage. I remember reading of how the Sea Harrier FRS1 gobbled F-15's once within Sidewinder range; did the FA2 do even better with Blue Vixen/AMRAAM in the package?
Although Stealth of the F-35 gives it a huge advantage in todays arena of long range radar and weapons, but that stealth could well disappear in the future. Advances such as quantum radar could well negate the stealth of the F-35, especially if one is made small enough to fit in the nose of a Harrier.
It may sound far fetched but a senior admiral of the USN a few years ago expressed concern that we are putting all our eggs in one basket regarding stealth. His view was that at some point technology will nullify stealthy designs.
Would that lead to a new lease of life for aircraft like the Harrier? A fraction of the cost of an F-35 but highly effective aircraft in that scenario. In reality the combat scenario will not stand still. When stealth is finally negated, probably there will be no manned combat aircraft and laser weapons will be used to shoot down aircraft.
But these stats show just what an effective aircraft the Harrier was. I doubt we have got as much value for money in any other fighter except the Spitfire and Hurricane.
I do love this common belief that the issues around the Harrier's wing/engine locations were somehow evidence of poor design. At the time it was designed V/STOL was essentially restricted to single-engine configs because engines (any engines) weren't deemed reliable enough to ignore the unmitigatable risks relating to asymetric engine failures in jet-borne flight. A large number of alternative VTOL mechanisms were tried, but with the materials and technologies of the day the only one that came even vaguely close to practicable was direct vectored thrust, and that meant that the engine had to be placed at the CG so that the trust centre was in the right place with the nozzles down. This inherently means that the engine has to be with the wing in the middle of the fuselage, because traditionally aerodynamicists prefer to have the wing close to the CG as well.
So you have two choices - engine above the wing or engine below the wing. Experiments showed that putting the engine above the wing resulted in bleeding great holes being blasted through the wing when the nozzles were vertical [/sarcasm mode] so Hawker opted for putting the wing on the top, over the engine. That meant the fuselage structure had a large hole in the top, so it needed strong sides and belly structure to compensate. Of course it also needed some strong structure to mount the undercarriage which (again by tradition) is generally put underneath the aeroplane where the ground is expected to be.
So an inherent consequence of the basic requirement is that the engine has to be in the middle of the fuselage with the wing above it, and the wing will have to be removed to get the engine out because it's not possible to create a big enough underside hatch whilst maintaining the required fuselage strength/stiffness at an acceptable weight. This means that WHATEVER we did you would still have to remove the wing to take the engine out.
Now another bit of tradition meant that the main undercarriage also needed to be put just behind the CG, but this space was already taken by the hot efflux from the rear nozzles.The available solution was the bicycle undercarriage with outriggers. Perfectly good solution, but it had the minor consequence that you had to trestle the fuselage before removing the wing. But again, there really weren't that many options within the weight/thrust characteristics of the only available engine. So all of this was just the inherent consequence of deciding to build a V/STOL aeroplane in the late 1950s.
The need to jack the aircraft, retract the U/C and then lower the aircraft was nothing to do with the Harrier. This was only needed at sea due to the restricted headroom available in the CVS hangar deck. The RAF never did it (they just trestled the fuselage), so if anything it was a design fault in the ship rather than the aeroplane.
All the rest of the issues fundamentally traced back to the fact that the MoD demanded the Harrier be a "minimum cost conversion" of a technology demonstrator. The MoD were (as usual) far too short sighted and parsimonious with the funding. In fact they were lucky to get even that, because the bulk of the funding came from the USA and Germany through Mutual Defence Fund money.
Now having said that, Hawker DID come up with a V/STOL design which eliminated most of these issues - the twin-boom P1216. It used a 3-nozzle development of the bigger BS100 engine, and the twin-boom layout allowed the mainwheels to be put in the booms so that the engine COULD just drop down on a trolley. But the MoD decided to buy american instead, so P1216 was cancelled, the RAF was stuck with the Harrier II and the RN was left to suck hind tit with further lashups stretching the Harrier 1 to ridiculous extremes.
I'm a GR9 man through and through (cut me and you'll find KT816 flowing through like a stick of blackpool rock), but if it came to a straight comparison between the GR9 and the F35 I would certainly HOPE the F35 was significantly better - it damned-well should be given that it was designed 50 years later and is more than an order of magnitude more expensive. If it isn't then LM need to be taken outside and shot for ineptitude or fraud!
But perhaps the REAL test should be comparing one F35 with the >10 GR9s that you could field for the same money...
PDR
So you have two choices - engine above the wing or engine below the wing. Experiments showed that putting the engine above the wing resulted in bleeding great holes being blasted through the wing when the nozzles were vertical [/sarcasm mode] so Hawker opted for putting the wing on the top, over the engine. That meant the fuselage structure had a large hole in the top, so it needed strong sides and belly structure to compensate. Of course it also needed some strong structure to mount the undercarriage which (again by tradition) is generally put underneath the aeroplane where the ground is expected to be.
So an inherent consequence of the basic requirement is that the engine has to be in the middle of the fuselage with the wing above it, and the wing will have to be removed to get the engine out because it's not possible to create a big enough underside hatch whilst maintaining the required fuselage strength/stiffness at an acceptable weight. This means that WHATEVER we did you would still have to remove the wing to take the engine out.
Now another bit of tradition meant that the main undercarriage also needed to be put just behind the CG, but this space was already taken by the hot efflux from the rear nozzles.The available solution was the bicycle undercarriage with outriggers. Perfectly good solution, but it had the minor consequence that you had to trestle the fuselage before removing the wing. But again, there really weren't that many options within the weight/thrust characteristics of the only available engine. So all of this was just the inherent consequence of deciding to build a V/STOL aeroplane in the late 1950s.
The need to jack the aircraft, retract the U/C and then lower the aircraft was nothing to do with the Harrier. This was only needed at sea due to the restricted headroom available in the CVS hangar deck. The RAF never did it (they just trestled the fuselage), so if anything it was a design fault in the ship rather than the aeroplane.
All the rest of the issues fundamentally traced back to the fact that the MoD demanded the Harrier be a "minimum cost conversion" of a technology demonstrator. The MoD were (as usual) far too short sighted and parsimonious with the funding. In fact they were lucky to get even that, because the bulk of the funding came from the USA and Germany through Mutual Defence Fund money.
Now having said that, Hawker DID come up with a V/STOL design which eliminated most of these issues - the twin-boom P1216. It used a 3-nozzle development of the bigger BS100 engine, and the twin-boom layout allowed the mainwheels to be put in the booms so that the engine COULD just drop down on a trolley. But the MoD decided to buy american instead, so P1216 was cancelled, the RAF was stuck with the Harrier II and the RN was left to suck hind tit with further lashups stretching the Harrier 1 to ridiculous extremes.
I'm a GR9 man through and through (cut me and you'll find KT816 flowing through like a stick of blackpool rock), but if it came to a straight comparison between the GR9 and the F35 I would certainly HOPE the F35 was significantly better - it damned-well should be given that it was designed 50 years later and is more than an order of magnitude more expensive. If it isn't then LM need to be taken outside and shot for ineptitude or fraud!
But perhaps the REAL test should be comparing one F35 with the >10 GR9s that you could field for the same money...
PDR
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Why was the Pegasus chosen for the harrier? Is it a stupid question to ask if an Avon wasn’t more reliable? Forgive the naivite of the question.
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The need to jack the aircraft, retract the U/C and then lower the aircraft was nothing to do with the Harrier. This was only needed at sea due to the restricted headroom available in the CVS hangar deck. The RAF never did it
A RAF GR3 had an engine change down South using this method.
It certainly got interesting when the ship's bridge was asked to steer a steady course for an hour or so whilst the engine was hoisted up or lowered down and during the evolution they decided to heel the ship over and go zigzagging around the oceans.
As people who have changed out Harrier engines know, there is not a lot of room between the engine and airframe and it's more than easy to get your hands trapped.
All good fun though and a great way to annoy the fishheads below when lashing everything down or storm lashing aircraft/equipment during normal ops.
Last edited by Whinging Tinny; 6th Oct 2018 at 10:11.
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Wingless Walrus - the FA2 carried 5000lb internally and with 190 gallon tanks a total of 8000lb. I think that ‘Mogwi’s bunch’ in ‘82 used the 100 gallon tank which gave you a maximum of 6600lb.
For the chart to be right then the GR is indeed on internals only....and even then I’m not sure the figure for either is right in an operational sense.
The real world has a habit of making the differences less stark than the ODM or simulation would have you believe!
For the chart to be right then the GR is indeed on internals only....and even then I’m not sure the figure for either is right in an operational sense.
The real world has a habit of making the differences less stark than the ODM or simulation would have you believe!
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Same theory though. If your nose leg can withstand it, why wouldn’t you want it?
A tp once told me that an unexpected benefit was better yaw control than flat decks as the nose leg compressed on ramp entry. Not sure whether that matters - in the sense that more is good but adequate is still adequate!!
A tp once told me that an unexpected benefit was better yaw control than flat decks as the nose leg compressed on ramp entry. Not sure whether that matters - in the sense that more is good but adequate is still adequate!!
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Wingless Walrus - the FA2 carried 5000lb internally and with 190 gallon tanks a total of 8000lb. I think that ‘Mogwi’s bunch’ in ‘82 used the 100 gallon tank which gave you a maximum of 6600lb.
For the chart to be right then the GR is indeed on internals only....and even then I’m not sure the figure for either is right in an operational sense.
The real world has a habit of making the differences less stark than the ODM or simulation would have you believe!
For the chart to be right then the GR is indeed on internals only....and even then I’m not sure the figure for either is right in an operational sense.
The real world has a habit of making the differences less stark than the ODM or simulation would have you believe!
If memory serves me right, the carriers it flew from were in fact not carriers! They were 'through deck cruisers' that in effect were adapted to allow the Harrier to fly from them?
Harrier was such a unique aircraft and the pilot was greatly relied upon for its ability in the air. A challenging aircraft. The F-35 may be more capable and easier to fly, but if I had the choice of flying either I would pick flying FA2's off carriers in its hayday. Times change and the Harrier was the end of an era; the arena has changed. But that aircraft punched way above its weight.
"Never in the field of aviation, has so much been achieved, with so little."
As good as the F-35 is, I don't see that phrase ever being used for any other aircraft.
I'm relishing this thread. So informative and helpful without any of the usual carping, back-biting or snide put-downs... well, almost.
Thank you to those knowledgeable contributors who deserve 'likes' in abundance.
Thank you to those knowledgeable contributors who deserve 'likes' in abundance.
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Effortless, in very simple terms the Avon did not have enough thrust for a Harrier sized aircraft and being a turbojet was not the right “type” of thrust. The Pegasus being a turbofan moves massive amounts of air at a relatively modest velocity compared to a turbojet. A turbojet moves a smaller amount of air at a tremendous velocity. A turbofan is better for a hovering jet.
Thank you for the clear explanation. I guess my original post was prompted by a picture of the eflux of the F35. It reminded me of RAF and US pilots on lightning conversion at Colt. The US pilots tended to have full reheat on take of while RAF pilots tended to leave the ground more sedately.
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Winged Walrus - my only addition to what you wrote is to point out your two mentions of the pilots.
Flying the FA2, GR7 and GR 9 was a challenging treat. But the heroes of the Harrier world were the squadron maintainers and armourers - who kept all marks going in all conditions from windswept oceans to baking desert heat - and their brothers (and sisters) in arms - the yellow coats of the CVS deck. (Not that my division ever had many kind words for the chock heads!)
Flying the FA2, GR7 and GR 9 was a challenging treat. But the heroes of the Harrier world were the squadron maintainers and armourers - who kept all marks going in all conditions from windswept oceans to baking desert heat - and their brothers (and sisters) in arms - the yellow coats of the CVS deck. (Not that my division ever had many kind words for the chock heads!)