Tailhook Topics

by Tommy H. Thomason

Monday, June 21, 2021

McDonnell F2H Banshee Stores Pylons Location

Oops - I make a mistake in scaling the side view of the AERO 14 pylon, making it too long (the bottom view length is correct). I've revised the drawing accordingly and replaced it. Here is an illustration of the AERO 14 pylon.

Note that the side of the pylon scales to 8 inches in height.

This is a picture of a pylon in Larry's collection that was removed from a P2V.

The front end (left side) is 7.5 inches deep; the aft end is 6.5 inches deep. It was 32.75 inches long.

While working on another F2H project (click HERE for a work in progress), I finally realized that I had never seen a McDonnell document that identified the location of the F2H Banshee stores pylons by fuselage station (fore/aft location) or butt line (distance outboard from fuselage center line). A quick check also revealed that McDonnell F2H front and top view documents that show the pylons are inconsistent with respect to their location (in fairness, exactness in those particular drawings was not a requirement).

Fortunately Larry Webster lives nearby and has a disassembled F2H-3 in his backyard. He and I were able to get good-enough data using a tape measure to locate them within an inch or less. This is the result:

Note that with the exception of the pylons and the outline of the wing (which was taken from pretty good McDonnell lines and station drawings), the location of the rest of the detail is not quite as accurate and I may have included more F2H-3/4 features than just the fairings over the wing-fold hinges.

The odd placement of the stores pylons is the result of the F2H-1 not being required to have them (neither was the F9F-2 Panther). They first appeared on the F2H-2 and the goal was almost certainly to add them with minimal changes to the structure. There are eight, numbered from left to right.

They are all AERO 14As, which were capable of carrying either rockets or 500-lb bombs. However, actual loads varied with the size of the bombs. For example, eight five-inch rockets or eight 100-lb bombs were two options but a total of only two 500-lb bombs could be loaded and only on the two most inboard stations, 4 and 5.

The upper side of the two-inch wide pylons differed slightly in shape to conform to the lower wing surface and were numbered by station as a result.

 

Note that the two inboard stations, 4/5 and 3/6, are less that 12 inches apart, being squeezed between a large removable panel and the main landing gear. The stations on the outer wing panel, 1/8 and 2/7 are not only well outboard but staggered. Placing them outboard reduced the impact of the added weight on the wing structure. They may have been staggered because of either center of gravity or structural (including aeroelastic) considerations or both.

I previously covered the nuclear store option here: Nuclear Banshees

Another Banshee stores oddity is that the F2H-2B carried a nuke on number 4 station while the F2H-3/4 carried one on the number 3 station.


Tuesday, June 15, 2021

Sword 1/72 Grumman TBF-1 Avenger and Tarpon Mk 1

 A work in progress:

For a Hyperscale review and pictures of the sprues: http://www.hyperscale.com/2021/reviews/kits/sw72136reviewjb_1.htm

Sword Models has continued to build on their 1/72 TBF/TBM kit range by going back to the first Avengers, the TBF-1 (SW72136) and Tarpon Mk 1 (SW72137).


The Tarpon Mk 1 was essentially identical to the earliest TBF-1 with respect to the engine installation, middle crew compartment, and with one exception, the later aft fuselage windows. The significant TBF-1 differences from the TBM-3 were the engine installation and single forward firing machine gun. These are provided for by a new fuselage sprue.

 

In box and build reviews of the earlier TBF/TBM kits are available on line. Suffice it to say, the accuracy, detail, and quality of parts and decals are commendable, more than adequate to the purpose. Nevertheless, a few notes may be of interest.

Grumman was the winner of a 1939 competition for a new torpedo bomber to replace the relatively new TBD Devastator. Contrary to what appears to be a four-man crew in this photo of the prototype, there were only three although there were originally four crew stations.

The pilot sat up front, the "assistant pilot/bomber" sat immediately behind him with a rudimentary set of flight instruments and controls, and the gunner/radioman sat in the turret. However, the Bureau of Aeronautics suggested that it would be desirable for both the assistant pilot and the gunner to have access to the radio, which clearly could not be accommodated, or his parachute for that matter, in the turret along with a .50 caliber machine gun (his parachute was stored on the side of the fuselage above the cabin door; he did wear the harness). Moreover, the "bomber", more usually referred to as a bombardier, would use a Norden bomb sight located behind a window at the aft end of the bomb bay, for level-flight bomb drops.

In the TBD, the assistant pilot/bomber crawled under the pilot to access the bomb sight, which was located forward of the bombs.

The radios were therefore located back in what was called the tunnel underneath the turret along with a seat that could be folded down from the left side of the fuselage. An opening was provided in the right side of the bulkhead at the aft end of the middle crew compartment for the assistant pilot to move down to the tunnel position. It was certainly easier for him to get back there than for the gunner to get down there:

These were the original windows in the aft fuselage (note in the illustration above of the bombardier kneeling at the Norden sight that the window on the left side of the fuselage does not line up with one in the center of the door; they differ longitudinally by about one half  of the frame spacing).

This is the best picture that I could find of the middle seat.

No controls are evident other than foot troughs that would go to the rudder pedals and what appears to be provisions for a control stick. Also noteworthy are the arm rests and the lack of a shoulder harness requirement at that time. To access the passage back to the tunnel, the assistant pilot would climb down to his right.

In any event, the Navy decided to delete the assistant pilot requirement, permanently relocate the bombardier to the tunnel, and assign him the radioman responsibility. This was reportedly effective with the 51st TBF-1 and probably the cause for the redesign of the windows in the aft fuselage to provide more natural light at the tunnel position.

 Part of the reason for the move was probably the need to provide a location for more radio equipment, which more or less filled the center compartment although it was still accessible from the tunnel.


The Royal Navy Tarpons were delivered from Grumman with this later window configuration and probably no seat in the middle compartment but the Brits chose to reinstate the center seat (probably without flight controls) and replace the large window in the aft fuselage with a dome for better visibility downward. The gunner was assigned the radio responsibility as the "Telegraphist Air Gunner".

The Royal Navy practice at the time was to require a navigator for carrier-based aircraft, the thinking being that pilot needed all the help he could get to find the carrier on his way back. U.S. Navy pilots, on the other hand, were expected to do so on their own. Chart boards were provided that slid out from the instrument panel so they could plot their position relative to the movement of the carrier in their absence and be able to find it again without benefit of radio direction finding (this is a TBM-3 illustration).

According to Paul Fontenoy, the Royal Navy crewman aft of the pilot was designated as Observer, which covered. his responsibilities that included navigation, gunnery spotting, reconnaissance work, and level-bombing aiming.

The Sword kits provide both the early and later fuselage windows. The instructions aren't explicit about which should be deleted by being painted over but the marking and color scheme illustrations can be used as a guide for that. The access between the middle crew compartment and the tunnel is not represented but could be by simply modifying parts 14 (the forward and middle cockpit floor) and 7 (the aft bulkhead of the middle cockpit).

Two other small details to consider adding by reference to pictures (note that their presence was short-lived) are the light on the backside of the pilot's headrest (it signaled the other bombers in a formation to drop when the lead bombardier did) and an ADF loop under the aft canopy. Note that the fairing between the canopy and the turret (part C10) was retractable (the turret could be swung around to face up and forward) and probably one of the first bits of the actual airframe to be removed and never replaced.

The retracted fairing and the signal light:

The signal light:

And the ADF loop with the turret fairing slid aft:

Wednesday, June 2, 2021

Douglas A2D Skyshark

 Clear Prop is now shipping its 1/72 scale XA2D Skyshark kit.

Although I haven't done more than look at what's in the box, my impression is that this is a first class production, including the box. For illustrations, go to Clear Prop's website: https://clearpropmodels.com/cp_72005

Also see the Hyperscale review here: http://www.hyperscale.com/2021/reviews/kits/cp72005reviewbg_1.htm

There were two XA2Ds, BuNo 122988 and 989; six A2Ds were completed and flown of the initial production order of 10. Both XA2Ds were originally painted blue but the second one was subsequently stripped of paint before its first flight. All the production A2Ds were painted blue.

While this kit provides parts and decals for the two XA2Ds, my understanding is that all the parts needed for a production A2D are included except for the very different canopy. The XA2D canopy had flat sides and top like the F4D Skyray whereas the production canopy was rounded.

The XA2D sliding canopy was also large and mounted on top of the fuselage; the sliding portion of the A2D canopy was smaller and mounted on a large fixed fairing that was on top of the fuselage.

There were variations in the exhaust fairings on the sides of the fuselage in part to resolve heating problems on the aft fuselage. Flight test began with a simple oval opening in the side of a fuselage but at least two increasing larger fairings were evaluated on the first XA2D.

Interestingly, when flight test finally resumed with XA2D BuNo 122989, the exhaust was once again a simple oval with no fairing.

And at least the first two production A2Ds also had no fairing initially. However,  one was subsequently added to the first production A2D and appears to have been the final configuration.

Steve Ginter's A2D Monograph (Naval Fighters Number Forty-Three) is an excellent reference. Unfortunately, Steve no longer has any in his inventory. It is still available from Amazon but buyer beware that it might be a relatively low-quality print-on-demand version.


Saturday, May 29, 2021

A Kaman HU2K/H-2 Seasprite Introduction

A work in progress:

The Kaman Aircraft Corporation won a Navy competition in 1956 for a small, high-speed, all-weather utility helicopter. It was designated the HU2K but by the time it entered service it had been redesignated the HU-2. Kaman produced a total of 190 of UH-2As and-2Bs.* The only difference between the A and B was navigation avionics, the lack of a full suite in the UH-2B meant that it was restricted to VFR (Visual Flight Rules) only. Externally, they were identical: single engine, four-bladed main rotor, three-bladed tail rotor, and retractable main landing gear.

The following were the Bureau Numbers:

147202-147205: Prototypes (short nose and small tail wheel)

147972-147983; 149013-149306; 149739-149786; 150139-150186;151300-141355; 152189-152206

One problem with identifying the subsequent UH-2 variants from photographs using the Bureau Number is that most were conversions of the original 190.

The first was the UH-2C, which was now powered by two engines:

There were 57 conversions from A/Bs. Note that the rescue hoist is no longer retractable and there is a boom that swung out to put the rescue collar in the pilot's field of view. It has a wider vertical fin below the arc of the tail rotor with an airfoil shape providing a yawing moment to the left in forward flight.

Six A/Bs were modified to the twin-engine HH-2C.

These were armed and armored for combat rescue. A four-bladed tail rotor was required and the heavier gross weight necessitated a dual-wheel main landing gear. The bubble fairing above the rescue hoist allowed for a reel with 200 feet of cable. However, even with uprated engines, these were underpowered for the hot, high conditions in southeast Asia.

The somewhat misdesignated HH-2D addressed the hover-performance issue by deleting the armor and armament. A total of 67 conversions were accomplished to what was really a UH mission capability.

This example is on display at the American Helicopter Museum (https://americanhelicopter.museum/) at the Brandywine Municipal Airport in West Chester, Pennsylvania.

The need for ASW (Anti-Submarine Warfare) helicopters that could be deployed from small non-aviation ships and capable of seeking out and destroying submarines resulted in the next variant, the SH-2D that resulted in 24 conversions; the four-bladed tail rotor and dual-wheel main landing gear of the HH-2C were utilized:

The added mission equipment included a surface-search radar under the forward fuselage, a Magnetic Anomaly Detection "bird" that was deployed from a outrigger on the right side of the fuselage, a sonobouy launcher on the left side of the cabin, and a smoke bomb dispenser for marking the location of MAD contacts. It could be armed with up to two homing torpedoes but each displaced an external fuel tank.

There were two YSH-2Es, conversions from BuNos 149033 and 150181. these were configured with other ASW avionics for evaluation.

Both were eventually converted to be SH-2Fs.

The SH-2Fs were initially conversions of a total of 104 of the original 190 UH-2A/Bs. They were powered by uprated T58s. Other modifications included strengthened landing gear and a new rotor hub, neither of which is notable externally. However, the tail landing gear was moved forward to provide more clearance from the deck edge, making it easy to identify this variant.

At this point, the Navy was finally running out of H-2 airframes to convert but needed more SH-2Fs so Kaman received a contract to build 54 new ones (in some cases, fabrication reportedly included building parts on the original tooling and then modifying them on the tooling created to convert the original parts). The BuNos are 161641-161658; 161898-161915; 162576-162587; and 162650-162655.

In 1986, SH-2Fs equipped with FLIR (Forward-Looking Infrared) systems and other non-ASW mission equipment began to be deployed into the Persian Gulf for night and mine-detection missions; they were also equipped with missile-defense systems.

Last but not least, the U.S. Navy bought six more SH-2s, BuNos 163209-163214, powered by GE T700 engines and designated SH-2G, the so-called Super Seasprite. Additional SH-2Gs were created from former SH-2Fs and New Zealand procured five new SH-2Gs from Kaman.

Gs were also operated by Australia (briefly and unhappily), Peru, Egypt, and Poland.

*Clear Prop Models has recently released an all-new, excellent 1/72 scale kit of the UH-2A/B: https://clearpropmodels.com/uh-2a/bseasprite

A Paul Boyer summary of the kit in the October 2020 issue of Fine Scale Modeler:

 
 
Clear Prop is planning on releasing a UH-2C and an HH-2D this year in 1/72.
 









Tuesday, March 30, 2021

North American AJ Savage Model Kits

A work in progress; more later:

 I was surprised but pleased to see a release of excellent AJ 1/72 scale Savage decals from CTA (Cut Then Add), which is based in Moscow.

For more on this company's products, see https://www.ctamodels.com/

I was surprised mainly because 1/72 kits, with one exception, are hard to come by and building any of them has a higher degree of difficulty than the average kit builder might wish to cope with.

There are also accuracy issues, in part related to the differences between the AJ-1 and AJ-2 and among the AJ-2Ps.

The AJ empennage was redesigned after a fatal accident in flight test when a structural demonstration resulted in the empennage being torn off. The original one had a very large rudder, believed necessary for an engine failure shortly after launch and one-engine-inoperative wave offs (also see https://thanlont.blogspot.com/2010/11/one-if-by-land-two-if-by-sea.html). The vertical fin was enlarged in area, the rudder was reduced in area (but repositioned a bit farther aft to minimize the reduction in its control power), the dihedral was removed from the horizontal stabilizer, and the horizontal strake on each side of the fuselage above the jet engine tailpipe was removed. All surviving AJ-1s were retrofitted with this empennage and all AJ-2s were built with it.

Another change introduced with the AJ-2 (and later production AJ-2Ps) was a redesign of the flight deck. The AJ-1 had seats for two on the flight deck, the pilot on the left and the bombardier on the right. There was a third seat on the lower deck just across from the entry door. With the AJ-2, the third crewman's position was relocated to the flight deck in an aft-facing seat. This required that the canopy be raised and lengthened. The controls for the pilot were also changed from a stick to a control wheel and the throttle quadrant was moved from his left to the center console on his right.

For more details on the Savage, see https://tailspintopics.blogspot.com/2011/07/aj-savage-notes.html and https://tailspintopics.blogspot.com/2013/04/aj-2-savage-cockpit.html and https://tailhooktopics.blogspot.com/2013/01/aj-savage-bombardier-station.html

The AJ-2 also had a modified hydraulic system. The only external indication of this is a two-piece nose landing gear door in place of the AJ-1's single rectangular door.


Unfortunately, these differences between the AJ-1 and -2 were not realized by kit manufacturers. There are four 1/72 kits:

Airmodel vacuum-formed AJ-1:

You don't get much (basic shell and canopy, no landing gear, no propellers, no decals, etc.) and what you do get is pretty crude, particularly the canopy. With a significant amount of correction to the plastic provided and scratch-building/scrounging of detail parts, a presentable model from the "kit" can be created.

The Mk 4 bomb and trailer were from 12 Squared: good luck finding that. A drawing for scratchbuilding one is here: https://tailspintopics.blogspot.com/2011/07/getting-it-right.html

One interesting aspect of this model is that it looks about right even though it has major shape issues: for example, the wings are too thick but that is offset by the nacelles not being deep enough.

Rareplanes vacuum-formed AJ-2/2P:

The late Gordon Stevens basically created the vacuum-formed kit concept, producing examples of airplanes that no injection-molded kit company would consider offering at the time. His products are also the standard for this kit type in quality and appearance. His AJ-2/2P is no exception, augmented by additions from Hannants.

It has white metal details, excellent decals, comprehensive instructions, and fuselage halves that are actually the same size. Regrettably he did not have source material equal to his intentions and expertise and may not have been involved in the sourcing of the propellers, which are the kit's most obvious error:

The propeller diameter is about right (a little undersized but then so is the kit itself) but the propeller blade tips should not be quite as wide and the width of the blades should then taper in a straight line (somewhat less than it looks like from head-on because of the blade twist) to the hub.

The drawings that he relied on were also inaccurate with respect to the vertical fin (the red outline is from North American's excellent AJ-1 side view; the green detail is the AJ-2 from North American engineering drawings and almost certainly indicates the correct location for the horizontal stabilizer):

An unforced error was that he assumed the AJ-2 canopy was the same length as the AJ-1's, just with different frames. As a result, it is a bit too short.

The kit is also slightly undersized but that's not a deal breaker in my opinion. Tony W currently has a build post on Britmodeler HERE.

Mach 2 injection-molded AJ-2/2P:

Mach 2 appears to have used the Rareplanes kit as a basis. The fuselage halves are virtually identical in size and shape, as are the wings and the nacelles, so it is slightly undersized as well along with a vertical fin that is not quite long enough. However, the clearish cast canopy is that of an AJ-1 or early AJ-2P (it's also awful; I reshaped it and used it as a vacuum-form master for my Airmodel AJ-1 build).

It is possibly better than the average Mach 2 kit and certainly buildable. Replacing the canopy requires some skill but the other issues like redoing the imaginary flight deck and reshaping the top of the vertical fin are straightforward. And it is still available

This is a model from the Mach 2 kit with a replacement -2 canopy (it looks like the one in the Rareplane kit, which came with two of them) on display at Mosquitocon in 2014

                                                            Photo by Adrian Davies

Anigrand resin 1/72 AJ-2:

This is by far the most accurate AJ kit (full disclosure: I provided drawings to Anigrand for it and reviewed photos of the first casts). Note the cast canopy. The only flaw that I remember (the box is currently in the back of warehouse behind the Ark of the Covenant crate) is the tail hook.

This is what the AJ tail hook should look like:

This is an Anigrand kit built by Brett R:

 And another with a review by Scott Van Aken: https://modelingmadness.com/scott/korean/us/usn/aj2.htm

Nostalgic Plastic was the U.S. distributor for Anigrand and included extra decals and a CD with additional information and photos on the type that I created.

Other notes:

In order to minimize weight, North American provided the Savage with a cumbersome method of folding the wing and vertical fin. See https://thanlont.blogspot.com/2010/03/hell-it-wont-fit-ii.html

Because of its size, aircraft carrier captains tended to prefer that the AJs be based ashore and only flown out to the ship (where nuclear bombs were stored for safekeeping) when the balloon was about to go up. However, after it was repurposed to be an airborne provider of jet fuel, its popularity increased significantly, particularly in the western Pacific where alternatives to landing back aboard the carrier could be few and too far between. See https://thanlont.blogspot.com/2013/12/texaco-redux.html