F35 testing video
Discussion
Godalmighty83 said:
Sadly we may never get truly beautiful military aircraft again, the 'stealth' focus dictates certain angles and areas which have a massive effect on the design aesthetics, a fairly ugly compromise between reduced radar profile and aerodynamics. All the little doors and features are another compromise for a low radar profile while in flight, frankly it can be as ugly as it wants as long as it works.
I think all the doors and features are also a result of giving it a "fighter" engine in the right place, with a decent payload. I love the Harrier to bits, but the STOVL requirement made huge compromises in its "fighter" performance 
Relatively speaking the harrier was 'slow' in the top speed stakes but that is mainly because it had to punch above its weight for a couple of decades more then what the original designers probably had in mind and mach speeds was certainly not at the forefront of all the challenges of getting the original to fly. The old bird out-lived just about every mach 2 fighter ever made.
The fact that the harrier is still discussed and compared is a testament to its abilities over a long life of hard service but its hard to discount its shortcomings which are almost entirely down to the age of the design.
The fact that the harrier is still discussed and compared is a testament to its abilities over a long life of hard service but its hard to discount its shortcomings which are almost entirely down to the age of the design.
MartG said:
robmlufc said:
Looks like the reaction control ducts are hidden by doors in forward flight, wouldnt fancy one of those failing to open when your coming into hover!!
I suspect quite a few of them will be lost due to a small door failing to open when requiredIt is a multi-stage conversion (8 IIRC) from wing-bourne to jet-bourne. It looks seemless, but the aircraft software checks every stage for completion before moving to the next. I'd share it but I believe it's classified for those in the industry only.
Furthermore, conversion from wing-bourne to jet-bourne, is the 'fail-safe' for the RollPosts as there is a 'large' positive pressure of the bypass flow pushing doors and actuators out.
Re the Harrier control systems, the X-35B test pilot explained to us on the Project that the Harrier pilots, when landing jet-bourne, had to effectively do a double integration in their head to convert a thrust command on the throttle into speed, then into position. The control sytem on the F-35B blends the pilots input into a pure position command and suitable response by the aircraft. It's clever stuff.
Ginetta G15 Girl said:
Really?
25,000 lbs of thrust is not very powerful?
As for slow, the Harrier was one of the fastest accelerating jets between 300 and 500 Kts.
Or did you mean 'sub-sonic', because, of course, you have to be super-sonic to be a good warplane.
25,000 lbs ish thrust isn't very much with the high lapse rate of that bypass ratio though is it? And while it may be able to accelerate quickly, this is partly due to the high wing loading; At 500 knts I'm guessing it would bleed a LOT of energy in a turn.......25,000 lbs of thrust is not very powerful?
As for slow, the Harrier was one of the fastest accelerating jets between 300 and 500 Kts.
Or did you mean 'sub-sonic', because, of course, you have to be super-sonic to be a good warplane.
Re: wrong pointing elevators
I'm guessing, and an aero guy might have more of an idea, but I think it would be to increase the lift coefficient of the overall a/c, hence the upward lift force, somewhat like flaps on a wing, to help it get airborne.
Pitch should be controlled by the thrust balance between the LiftFan and 3BSM
I'm guessing, and an aero guy might have more of an idea, but I think it would be to increase the lift coefficient of the overall a/c, hence the upward lift force, somewhat like flaps on a wing, to help it get airborne.
Pitch should be controlled by the thrust balance between the LiftFan and 3BSM
doogz said:
..the rather tired airframes...
There was nothing tired about those airframes, they would have quite happiliy carried on into 2020 if required or until F35 finally turns up. Lone Wolf said:
Furthermore, conversion from wing-bourne to jet-bourne, is the 'fail-safe' for the RollPosts as there is a 'large' positive pressure of the bypass flow pushing doors and actuators out.
Thats interesting! Makes sense though. What happens if the systems finds a problem with the RCS system? Will it simply not go into 'hover'/STOL mode? Is there an emergency 'blowdown' system that can open all the required doors if required? Edited by robmlufc on Wednesday 11th July 07:45
Edited by robmlufc on Wednesday 11th July 08:20
Ginetta G15 Girl said:
doogz said:
Stuff.
Really?25,000 lbs of thrust is not very powerful?
As for slow, the Harrier was one of the fastest accelerating jets between 300 and 500 Kts.
Or did you mean 'sub-sonic', because, of course, you have to be super-sonic to be a good warplane.
Hooli said:
Shame we never built the P.1154 eh?
I watched a mid-80s documentary about the Harrier on youtube recently; the interview footage with the likes of Sir Stanley Hooker and other leading lights of the development was surprising, the general implication was that P1154 was very close to flying when the plug was pulled and showed promise far beyond the Kestrel. Mere months after that Harrier gets the go-ahead in another Great British Defence Procurement Mystery(TM).Gassing Station | Boats, Planes & Trains | Top of Page | What's New | My Stuff