Saturday, 4 May 2013

Comparing apples to oranges (Part1): Internal weapons.

One of the F-35's key selling points is its internal weapon storage.  This not only allows it to remain stealthy, but it "cleans" up the aerodynamics of the aircraft.  That is Lockheed's claim, anyway; and it is true to a point.

During the recent "CF-35 Webinar"(available here), Lockheed test pilot Billie Flynn often implies that, because the F-35 carries its weapons and fuel inside, it is more aerodynamic and stealthy than traditional aircraft.  This is true...  To a point.

Bomb truck.

A traditional fighter aircraft loaded up with missiles, bombs, and external fuel tanks will indeed handle much differently than one that is unencumbered.  Extra weight, extra drag, and changes to the aircraft's center of gravity will make it slower and clumsier, no doubt about that.  An aircraft capable of mach 2 "clean" may be reduced to subsonic speeds at best.  Since the F-35 carries it all inside, that means an "loaded" F-35 must perform better than a "loaded" 4th generation fighter...  Right?

This (assuming 2 BVR and 2 WVR missiles)...
...equals this.
Not this.

The F-35 carries a maximum of 5000lbs worth of ordnance internally.  That is divided up amongst 4 hardpoints.  Two of those hardpoints are restricted to AMRAAM storage only.  That means, for an air to air role, an F-35 is restricted to a maximum of 4 missiles, two of which must be AMRAAMs, while the other two may be either AMRAAMs or ASRAAMs.  The F-35 does have the option of storing additional weapons on pylons, but this throws the F-35's stealth and aerodynamic advantage out the window.

To compare, a 4th generation fighter like the Gripen stores all of its missiles and extra gas externally.  However, if you compare the actual payloads, you will see that adding four missiles and some fuel (as in the middle picture) doesn't really add a whole lot of bulk.  As an added bonus, as fuel is used and missiles are fired, the Gripen in the (above in the middle) will only become lighter and more sleek, especially if the drop tank is jettisoned.

"Fully loaded" F-35.
Fully loaded Typhoon.
Fully loaded Gripen.
Above is another example.  Notice the three jets are all "hogged up" with missiles, bombs, and external tanks.  The F-35 up top is still the "cleanest" of the three, carrying two JDAMs internally for a total of 6 JDAMs, 2 AMRAAMs, and 2 AIM-9X Sidewinders.  The Typhoon in the middle carries less bombs, but carries a whopping 6 guided missiles (2 IRIS-TS and 4 AMRAAMs and/or Meteors).  The Typhoon also has three large external fuel tanks.  The Gripen at the bottom is seen carrying 2 anti-ship missiles, 4 laser guided bombs, a LITENING pod, 4 Meteors and 2 wingtip IRIS-Ts.  These are all comparable loadouts (focused on ground or surface attack) with heavy, if not identical weights.

Again, as the Typhoon and Gripen release their weapons, their aerodynamics will improve substantially.  Once they release all but their air-to-air weaponry, they will be capable of supercruise, as well as being able to fulfill an air-superiority role with 6 missiles.

The F-35 in the above example, however, will now be at a disadvantage.  It only has 4 air-to-air missiles, and its most vaunted feature, stealth, will be severely compromised by the addition of the external pylons.  It could still be stealthier than the other two, but it is still slower and less well armed.

The F-35 does have a much better range than the legacy CF-18 without external tanks, but so do the Gripen E, Super Hornet, and Typhoon.  So again, comparisons must be based on range. It is important to note that aircraft burn through fuel at different rates. For example, 450 gallons of fuel will go further in the smaller, single engined Gripen than the bigger, twin-engined Typhoon.

Okay...  This might be a little much.

It is important when comparing these fighter aircraft to do so with similar missions and payloads in mind.  Comparing one fighter with a light load of air-to-air missiles against another with heavy bombs and fuel tanks is disingenuous.


  1. The f35 because of the internal stores is also a fat airplane. That's why despite having a very powerful engine it has a very slow acceleration from high subsonic to supersonic. And this problem is always there unlike fighters with external fuel tanks. The gripen can jettison it's external fuel if it needs to fight to live.

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    1. Once again, you're getting too carried away with nitpicking numbers... And missing my point entirely. Again, if the F-35's internal payload is to be said to give an advantage, then it should be compared to other fighters flying no more than 5,000lbs of weapons on 4 hard points, with similar range (not fuel, since different aircraft will burn through fuel at different rates).

      Sorry I couldn't find picture of a Gripen carrying 12,000lbs worth of JDAMs. Then again, I couldn't find one of the F-35 carrying it either, outside of a video game screen capture. As I stated, the pictures were merely supposed to represent similar (ie ground attack) load outs, with similar (heavy) weights. I'm sorry if you were under the wrong impression there, I'll alter the article.

    2. For a more detailed look at the F-35's internal weapon superiority claims, as well as its air-to-air performance, please check out this article:

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    4. I don't know how many different ways I have to spell this out: Fighter X with Z pounds of payload should be compared with Fighter A with Z pounds of similar payload. Both should be capable of the same range. Full stop. Period.

      Yes the F-35 internal bays can be an advantage. They can also be a disadvantage.

      "The only way to get a Gripen to lift what a JSF or Eurofighter can is to use two Gripens" Indeed. The JSF is a better bomb truck. Possibly one of the best.

      Please explain why Canada needs a stealthy bomb truck as opposed to a cheaper, faster aircraft that was developed with more focus on interception duties. Will 18,000lbs of bombs help keep Canadian airspace safe? Does Canada need a massive payload so we can carpet bomb our many enemies into submission? Do we need stealth in order to carry out the RCAF's mission of preemptive strikes?

      Again, I ask you: If you believe that the F-35 is the best choice for Canada, explain why. Why is it better than the Gripen? Why is it better than the Typhoon? Why is it better than the Rafale? Why is it better than the Super Hornet? You don't like the Gripen? Fine, I get that. Why is the F-35 better for Canada? It's not a hard question, but you have yet to answer it.

  3. Good point. The argument for the F-35s advantage due to its internal weapon bays is quite limited, because the F-35 can only carry two AMRAAMS and two large bombs internally. In practice, this payload just doesn't cut it. So once you start adding external weapons, the stealth advantage diminishes and the aerodynamic advantage diminishes too.

    So the F-35 is not a good bomb truck because it has an abysmal payload when using internally stored weapons only. It's not a good air superiority fighter because it cannot dogfight and its not good for close air support because it cannot loiter above the battlefield slow and low.

    The F-35 really is no good in any mission.

    1. Actually, I do believe the F-35 may indeed be a decent bomb truck. It has the option of storing an small internal load while remaining stealthy, or a decent sized external load at the cost of stealth. This gives it a little more versatility. It has the option of sneaking into hostile airspace, dropping bombs, then sneaking out; or going in completely loaded when the airspace is rendered safe.

      It's in the air-to-air role, that things get a little more complicated. Does the F-35 go into combat with a small payload of 4 missiles to maintain its stealth advantage, or does it trade that stealth for more firepower? Ideally, the F-35 pilot will stay in the shadows and fire off an AMRAAM for a BVR kill. This goes on the assumption that the F-35's stealth works without fail, the AMRAAM (100-180km range) works without fail, and that the enemy force doesn't outnumber the amount of missiles. If the F-35 is detected by an IRST (approx, 90km range), all bets are off. No current stealth technology can hide a hot missile or a hot jet engine. On top of that opening the weapon bay doors or locking on with a radar will give away the F-35's position, if only momentarily.

      Fighter jets travel in packs remember, and with modern data links, only one fighter needs to see the enemy.

    2. Hi,

      some words about range :
      180km range for Amraam? What kind of fighter could be detected that far?
      90km range for IRST, that's amazing. I was thinking about half of that, at best! Have you some information about that?

      I agree F35 could become an efficient strike aircraft ( that is its first mission after all : "Joint STRIKE Fighter") but air-to-air performance remains questionable in my opinion. Depending on radar, missile and stealth performance, unknown yet, F35 could be decent in BVR combat. But for what reason could it possibly stands a chance in WVR combat against a modern agile fighter featuring canards or thrust vectoring?

    3. The 180km range is for the latest AMRAAM, the AIM-120D.

      Information for the PIRATE IRST can be found here:

      The detection range is even better when viewed from the rear, thanks to the big hot jet engine.

    4. Thank you,

      your link is only a blog (though maybe well informed).

      That's amazing, There is little official data about IRST range. That's the same with AMRAAM. All that I found are CONcepts of use in USAF and RAF website, not very high(between 40 and 60 km!). Manufacturers discretion seem to be very high about so important data...

      180km range for AIM-120D remains optimistic in my opinion : The significantly heavier Meteor is claimed to be a 100km-class missile!
      But, 180km is maybe possible for a slow moving target, not very agile, and at low altitude.... wait.... an helicopter? :-D

    5. It's hard to pin down an exact range when it comes to those things. For an IRST, range will be highly dependent on the target's heat signature, as well as other factors. Obviously, a big 4 engined bomber will likely give off more heat than a single engine fighter.

      As far as the AMRAAM's range goes, again, it's highly variable. Depending on the target's RCS, the altitude, the speed, direction, it's all a factor. It's likely the numbers published are based on a "best case scenario".

    6. There is a big confusion regarding the range of AAM's. What is often advertised as range is really maximum launch distance in a head on scenario.

      The missile is simply calculated to be launched with the target outside its own kinematic range. The target is expected to close the distance by itself during the missiles flight time. The AIM-120D "range" of 180km might be correct if calculated that way, but certainly not for tail chase. It would also have very little energy left at that distance and have quite difficult against a manoeuvring target.


    7. Exactly. That's one of the biggest selling points if the MBDA Meteor, its ramjet propulsion allows maintain its energy throughout its flight.

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  5. @Doug
    Don't let this troll get to you beacuse he will never get it. He is a F-35 fan boy who belives 100% of the LM propaganda and belong at sites like "" were people can't think and thrash talk everone who don't drink the LM coolaid.

    He will never get that money is an issue (a huge one), if not now then in the near future and he will nevet accept that any other plane then the A... sorry F-35 is "good enough" for Canada.

    You don't have to show him any more respect beacuse he is not showing you any...

    Go and troll some other blog, you are pathetic...


    1. I believe that people should be able to have their say, and I would very much like "nickname goes here" to make an argument for the F-35 and how it would fit into Canada's defense strategy.

      I'm pretty certain that we (nickname and myself) are unlikely to agree on much, and that's fine. But I feel that if I were to say that "the sky is blue"; nickname go to great lengths to assure me it is not, but then avoid telling me what color the sky is himself. I have asked him that if he believes that the F-35 is a better choice for Canada, then he should make his case, not only against the Gripen, but for the F-35.

      As I have mentioned before, I believe that the F-35 will be an excellent strike fighter. But why does Canada need a stealthy strike fighter? Why not something cheaper? Why not something capable of supercruise? Stealth is nice, but is it really that big of an advantage that it renders all else obsolete?

      If nickname believes that the F-35 is best, then he should be prepared to make his/her argument, and be willing to let that argument come under the same scrutiny that he/she has addressed to me. Anything else just denigrates to a shouting match.

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    1. Since you insist on rambling without saying much, spouting vitriol and accusing me of various things, I am now deleting all your posts from here on out.

      I've given you more than a fair chance to make your point. To have your say, but instead, you seem to devote all your energy to being a negative force on this blog.

      Goodbye. Go troll somewhere else.

  7. Good riddance! Time and time again, in post after post you have asked him to provide his argument why the F-35 would be better for Canada and again he is just avoiding the challenge while instead doing his best to snipe others arguments in an unfair and improper way.

    Regarding the aircraft: You forget to mention that having a record high sortie rate like the Gripen to some extent makes up for being able to carry less heavy bombs than the bigger planes. Or you can use more planes. This is mostly in a bombing context. The Gripen can be at a disadvantage if the discussion is focused on hauling bombs as part of an invasion force. If the context of the discussion is for example dog fighting then the Gripen has a distinct advantage (as has any modern plane vs the F-35).

    I believe things like well trained pilots, superior sortie rate and cost efficiency are more important for Canada than being able to sneak in a couple of extra JDAMs in Iraq or Afghanistan. /Tor