F4U Main Landing Gear Door Attachment

One incorrect assumption that plastic kit manufacturers make about the shape of the forward-facing main landing gear door on the F4U Corsair is that the opening is the same shape as the door or vice versa. The problem is that the opening between the top of the door and the front of the opening was closed by a piece of leather or rubber; the opening extends farther forward toward the wing leading edge than the door itself covers. Here you can see the flexible gap-filler material doubled over on a restored Corsair.

And here it is with the gear up on the XF4U:

F-4 Phantom Forward Fuselage

Mark Nankivil provided me with a McDonnell lines drawing of the F-4B/J Phantom. Questions have been raised about the shape of the Academy 1/48 F-4 nose. For what it's worth, here is the forward fuselage with a reference box for scale.

One interesting feature is that the break between the radome and the fuselage is not perpendicular to the line of symmetry of the ogival radome, which is what you'd expect.

The IR sensor fairing side view and cross section:

Douglas DT-2

Yet another draft based on an IPMS Tailhook Topics column.

The Douglas DT-2 was one of the U.S. Navy's first torpedo bombers. It was operated as both a seaplane and from Langley as shown here.

It was based on the Douglas World Cruiser, which the Army flew around the world in 1924. The major external changes were:

- Cut-down upper aft fuselage
- Rear cockpit moved aft
- Front cockpit opening larger and squared off
- New nose, vertical fin and rudder
- Recess in the bottom of the fuselage for mounting the torpedo
- No dihedral in the upper wing or center section cutout (there was also a fairing on the right hand inboard upper surface)
- Added cutout in the lower inboard wing to allow access to the cockpit when the floats were installed
- The horizontal tail was moved forward and enlarged accordingly
- Tailhook
- Initially, a propeller guard and hooks on the landing gear spreader bars to engage the longitudinal wires on the early arresting system

This is a pretty good drawing that I did back then from Douglas drawings provided to me by Harry Gann. Unfortunately, the tailhook is speculative. (Click on it for a larger and downloadable view.)

The torpedo was probably the Mk 7, which was 17 feet long and 18 inches in diameter:

F9F-2KD Regulus Controller Trainer

A Work In Progress

This airplane was used to train Regulus missile controllers. It was not a true drone since a pilot was required for takeoff and landing.

National Archives 80-GK- 23622

National Archives 80-GK-23623

Assigned to GMGRU-1. Pictures reportedly taken 29 June 1958 at Point Mugu.

F-4 Sparrow Missile Orientation

According to pretty good McDonnell F-4J drawings, the Sparrows mounted under the fuselage were angled slightly from wings level.

In the front view, it is clear that the rear Sparrows are angled. Using Illustrator, I measured it at three degrees.

The forward Sparrows appear to be not angled as much in the above front view but close examination of the cross section at the location of the forward Sparrow's aft wings indicates that they are rotated the same three degrees as the aft Sparrows so the wings lie flat on the surface of the bottom of the fuselage.

A-4F Laser Spot Tracker

From Scooter! plus subsequent information and illustrations:

The last carrier-based A-4s involved in the Vietnam War overlapped with the introduction of laser-guided bombs (LGBs). These were conventional bombs modified with a laser seeker, simple guidance computer, and controllable fins. The target was designated by a laser beam that the LGB could detect and home in on. The accuracy was outstanding, with the LGBs hitting within a few feet of the designated spot. The first laser-guided bomb drop at China Lake was made in early 1970, using a ground-based laser and a simple deviation meter in the cockpit of the A-4 carrying the bomb.

Since the Navy A-4s were in the process of being replaced, the implementation of laser designation capability was very limited. Some of the VA-164 A-4Fs deployed on Hancock with Air Wing 21 in 1973 were equipped with a Laser Spot Tracker (LST) in the nose and a Ferranti gun sight that displayed the spot being designated by a laser in another aircraft or by a person on the ground.

Independent of a similar U.S. Air Force program effort, China Lake had developed a hand-held designator, known as the Light Weight Laser (LWL). Roughly the size of a cigar box, it could be installed in a TA-4, A-6, or F-4 in about 45 minutes.

Via John Bittick

Six LWL units were fabricated and distributed to selected squadrons for combat evaluation, one of which was VA-164. To provide the designation capability, VA-164 borrowed two TA-4Fs configured with armor and ECM avionics from a Marine unit based at MCAS Iwakuni, Japan. These were reportedly BuNos 154325 and153491.

 

Note that VA-164 would also have had TA-4s assigned while shore-based for instrument proficiency, etc. like BuNo 152877. While it is shown here on a carrier, it doesn't have the ECM suite:

BuNo 154622 was another TA-4 assigned to VA-164, also side number 416.

Via John Bittick

The squadron Ordnance Warrant Officer and LDO Assistant Maintenance Officer, both non-pilots, volunteered to be trained in the operation of the LWLs and fly in the back seat on combat missions to provide designation of the target while the pilot in the front seat circled it.

 

The pilot of an accompanying single-seat A-4 dropped a laser-guided bomb on the spot.

In spite of the limitations (the 8-pound weight of the LWL precluded the TA-4F pilot from pulling any g load if the guy in back was to hold the spot steady), the trial was a success. The TA-4F would precede a small strike group by 2 miles and search for targets of opportunity, flying at an altitude of 5,000 to 7,000 feet, which was above the effective range of small arms fire. When a suitable target was spotted, the TA-4F pilot would pull up and circle it at 10,000 feet while the observer would begin to designate it. Laser designation was also useful for attacks employing non-laser-guided munitions, since the pilots flying the LST-equipped A-4s could use the laser spot in lieu of smoke rockets or geographic references to locate the target that had been found by FACs.

The successful trial proved the validity of laser designation and the LST hardware for development and adoption in the final iteration of the Skyhawk.

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: http://www.ginterbooks.com/NAVAL/NF26.htm

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

Also see the review here: http://modelingmadness.com/scott/viet/previews/anigrand/aa2060p.htm

See http://www.modelingmadness.com/scott/korean/xf10fpreview.htm 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: http://www.britmodeller.com/forums/index.php?/topic/234938495-172-grumman-xf10f-1-jaguar-finished/

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:  http://web.ipmsusa3.org/content/xf10f-1-jaguar