by Tommy H. Thomason

Wednesday, October 28, 2009

F8U Crusader Variations

29 January 2017: Updated with a revised UHT (Universal Horizontal Tail) illustration

For the best single reference on F8U-1/2 configuration differences, buy Squadron Signal Publications Walk Around Number 38, F-8 Crusader by Ed Barthelmes. It includes details that I hadn't noticed or knew about, copiously illustrated in color.

For a summary of Crusader armament changes, see http://thanlont.blogspot.com/2013/03/a-brief-history-of-f8u-crusader-armament.html

This is another work-in-progress. I got a request for this particular one and since I had done some work on it, I've decided to post it and perfect it later. For a bigger picture, click on it.


 


F8U-1 Notes

The solid nose wheel was introduced with the F8U-2N (F-8D) and retrofitted to earlier production Crusaders as they came through overhaul, so there isn’t anything like a BuNo (other than 147037 and sub) or date certain that can be used. There are also examples of Es and possibly even NEs with the spoked nose wheel, but these are almost certainly shore-based airplanes taking advantage of built-up spares.

Here are pictures of the early spoked nose wheel hub:


The tendency of an F8U to land on the nose wheel, particularly after an in-flight engagement, may be why the Navy went to a solid hub nose wheel. One of the tenets of good design is that you don't make something relatively cheap and easily replaceable so strong that instead of it breaking in an overload situation to relieve the load, something else does that's expensive and/or very hard to replace or repair.

The early main landing gear wheel was also different.



According to my notes, the Sidewinders and refueling probe were added to 143701 (F8U-1 production #66) and subsequent. Note also that the spoilers for better lateral control weren't added until 143771 (#136) and sub.

Also the small inboard flap was incorporated on production #17 and sub, although this and probably the refueling probe/Sidewinder and wing spoiler installs were retrofitted to at least one of the early aircraft for test and evaluation purposes. (e.g. BuNo 1440446 had the inboard flap for the carrier trials on Forrestal in April 1956)

Vought Ejection Seat

A later external modification to the Vought seat involved increasing the depth of the pad on the head rest so it extended down around the shoulder harness attachment:

It was installed as late as early F8U-2s before the change to the Martin-Baker seat and retrofitted to earlier production including the F8U-1Ps.

Tom (Superheat) Weinel did some great work on describing and depicting the differences between the various F8U models and modification. This is one of his illustrations, the radome shape change between the early Crusaders and the F8U-2NE (F-8E).



One unusual feature of the four-Sidewinder installation is that none of the missiles are mounted at the same angle in order to clear its partner on the Y-mount as well as the in-flight refueling probe on upper left side and the ram-air turbine on the lower right. Some kit manufacturer haven't gotten this right. Bill Gilman reports that Academy did with its 1/72 F8U but neglected to provide adequate instructions as to which pylon went where.
The F8U-2NE was to be armed with Bullpup but the requirement for the capability was cancelled before qualification was completed, which is why there aren't any pictures of it on deployed F-8s. (Early -2NEs, perhaps 149XXX, were delivered without the Bullpup fairing; it was retrofitted however, and used to house ECM avionics.) If you want to hang something menacing on the wing pylon, consider a WWII 2,000-lb bomb.

The F8U-1P/RF-8 wing, empennage, and fuselage from the main gear wells aft was basically the same that of as the F8U-1/F-8. The RF-8 was a little over three inches longer than the F-8s with the small radomes but only because of the pitot sticking out over the nose. The fuselage ahead of the wing and below the cockpit was modified to introduce more of an area rule effect and provide flat surfaces for the camera windows. As a result, the inflight refueling probe was now housed entirely within the fuselage and the fairing above the forward part of the wing was deeper and wider. The nose cone changed as well to incorporate the periscope window and the pitot.



 For more on the photo Gator, see http://tailspintopics.blogspot.com/2013/12/photo-gator.html

12 comments:

  1. Nice, dense, information. A fellow fan and model builder thanks you! I remember eating hamburgers and watching F-8 take off at dusk in the San Diego area, summer of 1963.

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  2. Any photos, comments about F8U-1 rocket pack lowering in flight, or launching rockets?

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  3. Well, here's an excellent website that I did not know about ... Thank you!

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  4. The Academy 1:72 F-8J kit seems to have the Sidewinder mounting correct. Here is my build of it:

    http://i1226.photobucket.com/albums/ee406/wrgilman/Vought%20F-8J%20Crusader/100_5708.jpg

    I don't know about the other Academy 1:72 kits, but the F-8J Sidewinder pylons and missiles assemble to look like your drawing. What's unfortunate is that Academy doesn't include a sketch showing you how to do this. As a result, I think a lot of modellers get it wrong. I wondered why the model's mounting pylons weren't symmetrical, which led me to do some research on the net and I found this page. Once I saw that, it was easy to get things in the right position. Great work, Tommy!

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  5. Did F-8Ds have the IRST dome removed when they were converted to F-8Hs?

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    1. Very likely and if not then, at some point in the future. According to Bill Spidle, who wrote a book on the F8U, the AN/AAS-15 was removed by AFC 525. It was probably in effect during the D to H conversions since it was released prior to May 1967 and the first delivery of an H was 29 August 1967. It's possible that the first few were missed and the AFC accomplished subsequently.

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  6. Were any F-8 variants ever equipped with pylons with plumbing for fuel tanks?

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    1. I went to my F8U subject matter expert, Bill Spidle, to be sure about this: there was no plumbing in the D/E/H/J pylons for fuel

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  7. Do you have any information or photos of the cockpit layout for the DF-8A and DF-8F Drone Controllers and target tugs?

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  8. I'm very late to this, but having been one of the engineers responsible for supporting the last RF-8Gs in the mid-1970s I can offer one insight here. The wheels were in fact changed because the original ones had been made of magnesium in order to save weight. But too many times (as photos vividly show) a hard landing would burst a tire and bring the magnesium wheel in contact with the deck at high speed, and the wheel would ignite. Switching to steel was a safety measure. There was a lot of magnesium in the F-8, and it all caused problems eventually. While I was at NARF Norfolk we did something called ARP (Analytical Rework Program) which basically involved un-manufacturing a sample aircraft, starting with removing the outer skin panels and working inward from there. We saw a lot of things that hadn't been visible since the aircraft was originally built, and the scariest involved flight control components. There were places where control wires had chafed through until only a couple of strands were left to carry the applied loads. But the bellcranks - wow! They were magnesium, and what I used to hear was "magnesium comes from the sea, and it always wants to return to the sea." Years and years of salty air had reduced the bellcranks to sponges. There were holes, large and small, all through everything except the steel bushings that were pressed into the ends of the arms. I don't know if anybody took any photos of them, I've never seen any, but they sent a clear message: Don't use magnesium anywhere that you can't inspect the parts frequently, and have access to replace them when they go bad!

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  9. I was on the tiny engineering team supporting the last few dozen RF-8Gs in the mid-1970s, and the reason I was told for changing the wheels was because too many F-8s were being damaged or lost when the original magnesium wheels hit the carrier decks or land runways at high speed due to burst tires. There are lots of photos of the resulting fireballs, so the wheels were changed to steel, even though the new ones were substantially heavier. Magnesium in other areas of the aircraft caused problems due to corrosion, but that was a whole other story.

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