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F-35 Cancelled, then what ?

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F-35 Cancelled, then what ?

Old 7th Aug 2014, 09:38
  #5001 (permalink)  
 
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'No view out the back'?

Pilots of the previous Lightning would positively covet the view from the newbie, surely?
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Old 7th Aug 2014, 09:44
  #5002 (permalink)  
 
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Interesting explanation Engines. I'm curious though as to why the canopy arch was needed, when the F-16 (also used in a bird-strike-rich environment) doesn't require this vision-limiting feature.
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Old 7th Aug 2014, 09:57
  #5003 (permalink)  
 
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The F-16 has a rather sturdy HUD designed to cope with bird strikes, which the F-35 hasn't.
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Old 7th Aug 2014, 10:08
  #5004 (permalink)  
 
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Cheers Cold
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Old 7th Aug 2014, 10:13
  #5005 (permalink)  
 
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Nee worries.
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Old 7th Aug 2014, 10:19
  #5006 (permalink)  
 
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Guys,

Thought I'd reply.

Courtney, I've sat in the cockpit a few times. i'm not a pilot, but there is a view out of the back. Is it as good as a Typhoon? No. Is it better than a Tornado? Yes. But there is a view. The canopy sill slope upwards from the throttle starts from a very low position, and to my (untutored) eye, the view wasn't significantly compromised. But I'll defer to your far more relevant views.

As I inferred in my last post, there are designers who think that the push for ultimate cockpit field of view went too far in the 80s and 90s. There are certainly aircraft that took a significant 'hit' in terms of performance. As ever, pilots and results will decide. (Sea Harrier had a fairly limited view, but that didn't stop it doing fairly well, as I remember).

Bird strike. The figures are lost in my ever more addled memory, but I do know that the requirement for F-35 was far more severe than that levied on the F-16. (or the F-15). This drove the need for a thicker and tougher forward section. (UK had a key hand in this requirement). The canopy arch is, as I remember, is there to help handle the transition between the reinforced forward section and the thinner aft. (And people might like to know that Typhoon struggled to achieve its own bird strike resistance requirement).

Location of that arch was modelled and adjusted over a period to get all the pilot views included. The F-35C requirement has given it a very good 'over the nose' FOV. As ever, it's a compromise, like most real things in the world.

Best regards as ever to those trying to do the right thing (for everyone)

Engines
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Old 7th Aug 2014, 10:42
  #5007 (permalink)  
 
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Tornado has mirrors

OAP
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Old 7th Aug 2014, 10:44
  #5008 (permalink)  
 
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The F-35's helmet/sensors means that when the pilot looks behind him, he sees behind him. No?
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Old 7th Aug 2014, 11:57
  #5009 (permalink)  
 
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F-16 is also the only in-service jet with an 'unbroken' bubble, no? Not knocking anyone but it's perhaps therefore an unfair comparison (or, if you prefer, the pinnacle/zenith of something or other...).
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Old 7th Aug 2014, 12:08
  #5010 (permalink)  
 
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Yes Cold, I guess my question about the canopy rail was really meant for all types designed after the F-16. If they were able to attain pretty much perfection in terms of pilot visibility in 1974 with no obvious increase in the danger of bird-strike etc (surely there would have been a redesign in the last 40 years if there was an increased danger), then why has every aircraft (excluding the F-35, the reason for which you have given) retained the visibility-limiting rail?
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Old 7th Aug 2014, 12:15
  #5011 (permalink)  
 
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melmothtw, I really wasn't having a dig.

F-16 brought with it a lot of new thinking - a reclined (30-degree) seat to help g-tolerance, a side-stick controller, and that one-piece canopy (for which the HUD, as mentioned, took the pain).

It's not just the canopy which hasn't been emulated. The Israelis, for example, when designing the abortive Lavi, were already flying -16s but decided against a side-stick as they felt it was a liability if the pilot got injured.

But how do you give a pilot a superlative view? Why, you give him a magic helmet...
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Old 7th Aug 2014, 12:20
  #5012 (permalink)  
 
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Didn't think you were Cold. The F-16 canopy thing is just something that has perplexed me for a while. It appears to be the pinnacle of design, yet no other manufacturer has tried to emulate it in over 40 years (even the Lavi you mention opted for the rail).
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Old 7th Aug 2014, 12:31
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The F-22 has an unbroken bubble - quite heavy, I believe - but a moderate birdstrike requirement because it's not supposed to spend a lot of time where birds live. Two-piece lids are considered anathema from the stealth viewpoint, although (so far) the T-50 has one.

Also because it's not designed for low altitude operations, the F-22 can afford to jettison the canopy before ejection. The F-35 has to provide for through-the-canopy ejection using explosive cord and breakers on the seat - another reason for that is the forward hinge, I believe, which militates against jettison, but was adopted to some extent so that the hinge would be common across three versions.

In other news:

"We're being very cautious right now in what we're allowing the operational users to do with the airplane, because we haven't quite gotten to why it happened yet," the general said.

Remember when this engine issue was isolated and it was all going to blow over in a few days?
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Old 7th Aug 2014, 13:01
  #5014 (permalink)  
 
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I'm dying to 'hear' some of our 'their airships', and admirals, use the word gotten.
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Old 7th Aug 2014, 13:10
  #5015 (permalink)  
 
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Originally Posted by Onceapilot View Post
Tornado has mirrors OAP
Presumably wing mirrors...

I know, I know,
Hat, coat, door...
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Old 7th Aug 2014, 14:48
  #5016 (permalink)  
 
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LO and others,

It's interesting how much attention a potentially simple thing like a cockpit view can get. A couple of points, they may help.

The F-35 ruled out canopy jettison more or less straight from the start, mainly due to the need for rapid zero-zero ejection for the STOVL aircraft. The forward hinge design was chosen to help with signature, and also overall weight, as well as providing the best access. Many, many CAD studies and mock ups went into selecting that layout. The fan door aft of the cockpit also ruled out an aft hinge.

No breakers on the Martin Baker seat, as far as I remember. Just exit through the remains of the canopy once blown by the MDC.

As I said, the big difference between F-35 and most other US jets was the severity of the bird strike resistance requirement, which was stiffer than for any legacy US jets, and was pushed very hard by the UK in particular. That led to the need for a reinforced forward section, and the arch, to prevent deformation of the transparency under impact. I believe (can't be sure, but a decent guess) that a similar design process led to the Typhoon design.

Lockheed had all the info, intellectual rights and experience on the F-16 canopy design right there in Fort Worth. They'd have used it if it met the requirements of the F-35 programme. It didn't, so they couldn't.

Oh, and the first fighter jet with a reclined seat (as far as I am aware) was the Lightning.

Best Regards as ever to those making the calls

Engines
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Old 7th Aug 2014, 15:18
  #5017 (permalink)  
 
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The UK Harrier II had a much tougher/thicker windscreen than it's US cousins for the same reasons - they were expected to spend a lot more time in an environment where avian hazards exist.

The F-16 was designed as a pure air-to-air dogfighter, and not to spend a lot of time down amongst the weeds.
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Old 7th Aug 2014, 15:27
  #5018 (permalink)  
 
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The F-16 was designed as a pure air-to-air dogfighter, and not to spend a lot
of time down amongst the weeds.
Yes, accept that Dave, but in 40 years of operations it has dropped more bombs at low level than most other types in service today. If there was a problem with the canopy design for this role, in that time there would have been a redesign...and there hasn't been.

Anyhow, I think I've had my canopy curiosity sated for now.

Thanks to all....
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Old 8th Aug 2014, 07:29
  #5019 (permalink)  
 
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The reason for the 30 degree tilt in the F-16 was to make the seat fit into the fuselage. LM pushed the so called g tollerence benefits, which are, at best, very slight. In truth there are some drawbacks, most notably the tendency of the pilot to tilt his head forward, very straining under g. Remember that most seats are inclined about 15 degrees anyway. F-16 gains more by raising the pilots feet.

As for cockpit visibility, this is a marked step backwards from, say, F-15. And, by the way, that has mirrors too.
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Old 8th Aug 2014, 11:25
  #5020 (permalink)  
 
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Can't be as bad as your Phantom though?!
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