Thursday, April 25, 2013

Why Does the F-35 Have Just One Engine? Blame It On Those Damned JarHeads.

A huge limiting factor of the F-35 is that it has just one engine.  In a vast, sparsely populated country with extreme weather (yes, that would be Canada), twin-engine reliability is a huge bonus.  One engine goes out - from a bird strike or mechanical failure, whatever - and you've still got one to let you limp back to the barn.

The F-35's vastly more capable big brother, the F-22, has twin engines.   So why just a single, massive jet engine for the F-35?  There is an answer.

When the F-35 was conceived it had to be designed to suit a lot of potential users.   It was supposed to replace most of the American fighter inventory.  That included the F-16, the F-18 and the AV8B, the Harrier.   That dictated three versions of the F-35, all of them sharing a somewhat similar airframe - similar but different.

The U.S. Air Force wasn't picky.   They wanted the ordinary, straight up warplane.   The U.S. Navy wanted a beefier version capable of operating at sea and withstanding the pounding of carrier launches and landings.   But - and there's always a "but" - the U.S. Marine Corps wanted a plane that could fly like their venerable Harrier jump jets.  The U.S.M.C. wanted a short-take off/vertical landing ground pounder.

The U.S.M.C. requirement meant that all three variants of the F-35 would be single-engine.   The airframe had to be designed to suit one big-ass boiler.   And it's for the convenience of the United States Marine Corps that Canada, and the rest of America's Aerial Foreign Legion, is going to have to bite it and go single-engine with all the problems and risks that entails.

Aviation Week's Bill Sweetman pondered what a twin-engine F-35 might look like.   Then it struck him.   It would look pretty much like this:






In case you didn't get the memo, that's China's new J-31 stealth fighter that has more than a passing resemblance to the F-35.   Some speculate that's because China is believed to have filched a lot of the design and computer code from F-35 contractors.




Oh well.

4 comments:

  1. Uh, this is a tad off topic.
    One of the shortcomings of the F-35 by many accounts is that it's a lousy dogfighter. I've gotten the impression over the years that there are always people concluding that what with planes fighting each other using long range missiles, dogfighting is no longer an issue, and there are always actual mock combat tests showing that ain't really so.

    What's your opinion on that? Would it be possible for a sort of flying weapons platform (not that the F-35 would make a good one of those either), with poor maneuverability but excellent sensors and electronics and a big payload capacity with plenty of good missiles, in this day and age to take on a more maneuverable traditional fighter? What if it was much cheaper, so you could have more of them--would the plane with better dogfighting capability be enough better to overcome say 3-1 odds?

    In the extreme case, for like air defence of a relatively small area like a city, what if you built like a small zeppelin with transparent, radar-invisible gas bag? Very slow, but capable of extended hover, hard to hit with heatseekers, and it could carry masses of armament and electronics. Could such a thing be remotely survivable?
    (OK, OK, silly I know, I just have this visceral fondness for airships)

    ReplyDelete
  2. The F-35 is, for starters, not a fighter much less a dogfighter. It lacks the speed, climb rate and turn rate to be a serious dogfighter. It lacks the range, payload and supercruise for the patrol or intercept role. It's way too expensive and vulnerable for the ground attack/strike fighter mission. It doesn't have the fuel capacity to loiter on station to meet the needs of troops in the field and would only be able to drop one or two bombs.

    It is a light attack bomber. Yes it can carry a pair of medium-range air to air missiles but that's far too few when you're likely to be seriously outnumbered by more capable defenders.

    The F-35 works as designed when it is not seen at all. Once it initiates an air fight it enters a different environment, one in which its vulnerabilities come out.

    Its stealth is frontal aspect only. The Russians and Chinese have worked out tactics that, even at long range, force the F-35 into a maneuvering fight that exposes its other five, non-stealthy sides.

    The bad guys will know when the F-35 is in the area when its refueling tankers and electronics support aircraft, utterly non-stealthy jetliner-type airplanes show up. Because of the F-35's limited fuel/range, these aircraft must accompany it forward where they also become extremely vulnerable.

    Once you know where the F-35s probably are, it's not hard to figure out where they're headed, the target they're planning to bomb, and then it's a matter of running grid patterns to pick up the bombers from their vulnerable, non-stealthy flank. With the proper deployment of defenders it should be fairly easy to spot the F-35 and once it is forced to evade missiles it has to turn at which point it's over.

    One thing that's often overlooked is that the F-35 was designed with a very large force of F-22s in mind. The F-22, upwards of 7-800 of them, was to fly cover for the F-35. Because of its cost and performance problems, Obama cut F-22 production at 170-fighters.

    Now it's a matter of math. How does a small force of fighters defend a large force of light bombers? Poorly. That's why the manufacturer and others constantly claim the F-35 is itself a fighter.

    As for the airship idea, I don't know how that would begin to work.

    The F-35 is intended to be sent into heavily defended airspace on stealth, i.e. surprise, bombing raids. It's not intended to dominate enemy airspace or anything else. That's a tiny little wedge of the air combat pie.

    For almost anything else, missions against Libya or Afghanistan, for example, conventional fighters backed up by electronics warfare aircraft actually work better.

    ReplyDelete
  3. It is only one way this mashine can be used to defend the airspace. It is by carrying very intelligent missiles into a position where they can be launched against an incoming enemy, and then fleing the scene. But these missiles must be equipped with multiple warheads that can be shooted one by one at individual targets. If something like this does not exist, then this thing is incapable to dominate the airspace.

    ReplyDelete
  4. Knut, I suppose the drawback to your idea would be the limited size of any such missile that the F-35 is capable of housing in its ordinance bays. If the technology you envision existed, would it not be simpler and cheaper to get it to the point of deployment via some form of unmanned vehicle?

    ReplyDelete