Wednesday, June 6, 2012

Grumman XF10F Jaguar Modeling Notes

No XF10F model—and surprisingly there are three kits in 1/72, three in 1/48, and one in 1/144—looks quite right to me. I finally took some time with a very large set of Grumman drawings provided to me by Rick Koehnen many years ago, two SAC-type three views, some XF10F articles from aviation enthusiast's magazines, and Steve Ginter's excellent monograph on the XF10F, which you can buy here:

Unfortunately, as usual there are XF10F three-views on line and in publications that do not meet a very high standard of accuracy, not to mention that each of the Grumman drawings are different in small details from photographs of the prototype as well as each other. That said, these are the views I came up with:
Note the relatively small canopy and the big aft fuselage (the XF10F was required to have an endurance of four hours, so there was a lot of fuel in the belly in front of and behind the main landing gear wheel well).
The wings pivoted around a post on the center line of the aircraft that moved aft when the wings were swept forward and forward when the wings were swept aft. Surprisingly, this feature was relatively trouble-free in flight test.
Note the large amount of anhedral in the wing.

These drawings represent the configuration of the airplane at roll out and first flight on 19 May 1952, which was brief. Before the second flight, a horizontal fence was added to the bottom of the vertical fin.
Also note the gap between the top of the rudder and the fairing that supported the horizontal stabilizer, which was also there for roll out. There was supposed to be a fairing there to cover the mechanism that moved the trim surface at the trailing edge of the horizontal stabilizer.

There were 32 flights in all before Grumman and the Navy gave up a little less than a year after the first one. For the 11th flight, a "diffuser" was reportedly added to the tailpipe "to move the tail pipe minimum area aft and reduce the boat-tail angle." I'm not sure what this looked like.

For the 17th flight, speed brakes and the horsals were added. The spoilers were supposed to double as speed brakes but were as inadequate for that as they were for roll control.

Note that the hook opening was sealed off after the sixth flight.

On the 23rd flight, the canopy blew out so on flights after this, there was a light colored reinforcement edge to the frame. The airplane was then laid up for 2 1/2 months for modification of the boat tail to reduce drag.
Also note that the fairing above the rudder is now in place.

The 24th, 25th, and 26th flight were accomplished with a larger horizontal tail. This was replaced with the original one for flights 27 and 28. A new turtle deck (the fuselage area over the wing) was also installed prior to flight 27 but I don't know what it looks like.

Flights 29 through 32 were accomplished with the powered horizontal stabilizer from the F9F-6 Cougar. The horsals were also removed.

Flights were made with various configurations of the aerodynamically actuated leading edge flaps: all operational, all of them locked up, and inboards locked up.

The wheel wells are natural metal but the landing gear and wheels are dark blue.

Unpainted main landing gear, flight position looking forward. Note length and attachment point for the upper V-link that moves the gear upward.

Modeling Notes to date:

The 1/72 Anigrand resin-kit wings are mounted on posts so they can pivot and "geared" so they pivot together. The kit features a movable wing attachment which is necessary to provide the correct wing position when swept versus unswept. However, the XF10F wings pivoted about a common point on the center line, so having two separate pivot points  would still result in at least one of the positions not being accurate

See for an in-box review of the Esoteric 1/72 vacuform kit. Pictures of a built-up kit are in the Ginter-published monograph.

I happen to have a 1/72 Planet resin-kit in work so I can verify that its nose is too long and the aft fuselage too short and not thick enough. The canopy is also too large, which appears to be a common failing of all the XF10F kits. However, it is now tan-tinted so it will have to be replaced in any event. The wing span is a little too large.

The main landing gear of the 1/72 Planet kit (there is also a 1/48th) requires modification to fit correctly. Assembly of the main landing gear strut is not accurately depicted on the exploded view and is a bitch – part #4 should be in line with the upper (shock) strut portion of the main landing gear strut (best you attach these parts to each other first) and only about half as long since it should attach about 5 mm below the top of the main gear well, on slots cut into the first stiffener – but not yet! First glue the attach fittings for the lower link, part #27, in place at the bottom of the gear well using the link, part #5, to get them spaced properly. That only leaves you with two loose pieces to try to glue to the gear well and each other at the same time…
Then the installation will look like the picture above.

The ejection seat is another problem. My guess is that the bottom looks like the Panther/Cougar seat:
But the headrest is blockier and probably integral with the lower portion of the seat structure like the earliest Grumman ejection seats.
In color pictures, it appears to be unpainted aluminum

To avoid a butt join of the wings and minimize the amount of weight in the nose, I cut an opening in the Planet fuselage for the part of the wing that was to be taken off if the wings were to be mounted in the swept-forward position with a butt join.

Here is an excellent build article for the 1/72 Planet XF10F:

The Mini Wing 1/144 kit provides two different wings for swept and unswept. It's hard to tell if the canopy is too big.

Here is a review of the Planet 1/48 resin kit: