by Tommy H. Thomason

Wednesday, January 29, 2014

Production F-111B Fuselage

Mark Nankivil has been scanning material from the Gerald Balzer collection and keeping me in mind when he comes across something that will be of interest to me. In this case, it was the McDonnell lines drawing for the production F-111B forward fuselage. McDonnell was involved with the F-111B program because they were the subcontractor for the crew escape capsule. When Grumman raised the canopy to improve visibility on approach for the production F-111Bs, McDonnell had to modify the capsule.

I had previously only had a few bits of data (fuselage length increase, windshield angle change, and height increase); a small and somewhat crude three-view drawing; and pictures of the sixth and seventh F-111Bs with the longer nose (but not the raised canopy) to work with. I also assumed that the capsule interface with the fuselage remained the same all around to minimize tooling changes. I was therefore surprised to see that Grumman, in addition to raising the canopy, had lowered the interface of the windscreen with nose, thereby further improving visibility over the nose. I had noted by reference to the pictures of the F-111Bs with the longer nose that they had lowered the radome slightly, which now makes even more sense.


On the two interim-production F-111Bs that flew, the upper side of the nose was modified from the production configuration to marry up with the forward bulkhead of the original escape capsule.

I'll note once again that the at-sea F-111B trials were conducted with an F-111B that did not have all the changes known to be forthcoming in the production aircraft (see http://thanlont.blogspot.com/2009/03/f-111b-carrier-trials.html). As a result, any deficiency related to visibility on approach was already being corrected.

For more on the F-111B, see http://tailspintopics.blogspot.com/2009/10/grumman-f-111b.html and http://thanlont.blogspot.com/2011/01/f-111b-versus-f-14a-one-more-time.html and buy my monograph, available on Amazon (http://www.amazon.com/dp/0942612418) or from Steve Ginter:


5 comments:

  1. Tommy- Any chance you have a top view to go with the side view? I can make an educated guess but a drawing would make creating a more accurate nose much less difficult.

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  2. Tim,

    Send me your email address at tommythomason(at thingy)sbcglobal(period)net.

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  3. Greets Tommy - sorry to resurrect this but, I just have to ask...

    I've been pouring over pictures of 152715 and -716 trying to find a definitive perspective that shows the raised cockpit was actually fitted those two machines - but I keep coming up blank.

    It is quite obvious these two jets had the escape pod from the many clear images of the panels around that area (though by looking at the seats, the pod may not have been 'live', like the early F-111A's), explaining the big nose profile 'ramp up' to the windscreen - but are we SURE these machines had a different canopy shape to the 151-series prototype F-111B's? And does anyone have a nice pair of say F-111A vs 152-series F-111B pictures that show the difference in canopy line, if the 'production' cockpit/canopy were in fact on 152715 and 716?

    Love the book, love the blog - many thanks for all youve done on both the F-111B and the MANY other works youve put together - particularly the Cutlass book (and muchly looking fwd to the new Cutlass book of yours in a few months - cheers)!.


    Dan

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    Replies
    1. Dan - Be assured that 715 and 716 were completed with the original capsule, since the production F-111B capsule was not available for their final assembly. As a result, you'll note in the picture and illustration in this post that there was a "ramp" added to the production nose to fair in with the front of the original capsule.

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    2. Thank you Sir - yes that was my initial understanding of that diagram... But the more I looked, read, compared, the more I think I introduced doubt in my own understanding! Cheers so much for your reply - it's very much appreciated! Just need to find some time to sit down and either a) 3D Model and print an F-111B Long Nose, or b) dig up some engineering board, and carve a B Long Nose; 715 and 716 are by far the best looking of the F-111B's ;)

      And again thank you for the awesome F-111B book (of which I actually have two copies) - and the forth coming F7U book!

      Dan

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