Project Tom-Tom flight tests began in 1955. They were intended to evaluate the difficulty of approaching the wing tip of the JRB-36F. RF-84F 51-1848 was fitted with a jaw capture mechanism on its right wing tip. The JRB-36F was equppped with a retractable scissors unit on its left wign tip. These light weight mechanisms were not intended to support the load of towing the Thunderflash.

Convair test pilots in the project included "Doc" Witchell, Raymond Fitzgerald, and Beryl Ericson.

Close-up of the left wing tip coupling on the JRB-36F. (Lockheed Martin Tactical Aircraft Systems negative 26-1807)

Jaw capture mechanism on the right wing of RF-84F 51-1848. (LMTAS negative 26-1804)

RF-84F 51-1848 approaches the left wing tip of the JRB-36F as a Lockheed T-33A flies chase over the Texas countryside in 1955. (LMTAS negative 26-1817)

Project Tom-Tom flight tests continued in 1956 with more substantial wing tip coupling mechnisms. RF-84F 51-1849 received a jaw capture mechanism on its left wing tip. The JRB-36F received a pair of wing tip coupling mechanisms that incorporated adjustable rear pitch locks. All contacts in this phase of Project Tom-Tom were to the right wing tip of the JRB-36F.

Close-up of the left wing tip coupling on the GRB-36F. (LMTAS negative 26-2294)

RF-84F 51-1849 suspended from a ground test rig to evaluate the functioning of the capture mechanism. Note the man under the Thunderflash holding the cables that are used to control its yawing. (LMTAS negative 26-2152)

Detail of the capture mechanism on RF-84F 51-1849 about to grab the right wing tip coupling of the GRB-36F during a ground test. (LMTAS negative 26-2160)

Overhead view of the wing tip coupling mechanism. Project Tom-Tom relied on a "skewed" hinge that was set at an angle. As the Thunderflash rolled around the wing tip, changes in its angle of attack generated restoring forces to keep it flying level with the wing of the JRB-36F. This eliminated the need for an electronic autopilot system. (LMTAS negative 26-2154)

RF-84F 51-1849 approaching the wing tip of the JRB-36F, 49-2707 late in the summer of 1956. (LMTAS negative 90-3082).

The JRB-36F tows RF-84F 51-1849. (General Dynamics negative 26-2290)

On Septemver 23, 1956, Beryl Ericson made contact with the wing tip of the JRB-36F with a small angle of yaw. Immediately, his Thunderflash started to flap up and down with increasing violence. There were no explosive squibs to break the connection between the airplanes, so the RF-84F escaped from the wing tip when the coupling mechanism failed. Part of the JRB-36F scissors mechanism remained stuck in the jaws on the Thunderflash wing tip. The incident ended Project Tom-Tom flight tests.

Damage to the Thunderflash was limited to some dents and scraping on the coupling mechanism.(LMTAS negative 26-2295)

Ver little damage is visible on the inboard side of the jaws.(LMTAS negative 26-2316)

The JRB-36F lost part of its wing tip couplilng mechanism. (LMTAS negative 26-2325)

Six turning and sixteen burning. Illustration from a NACA Research Memorandum written at the Langley Aeronautical Laboratory entitled, Calculated Lift Distributions of a Consolidated Vultee B-36 and two Boeing B-47 Airplanes Coupled at the Wing Tips. The memorandum is dated November 30, 1950. If the feat had ever been attempted, the wingspan of that monster would have exceeded 460 feet.

Other Flying Aircraft Carriers of the USAF

Flying Aircraft Carriers of the USAF

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Wing Tip Coupling

2013 calendar

You can buy a 2013 calendar featuring photographs of Air Force projects investigating the coupling of smaller airplanes to larger airplanes' wing tips.

In the early years of the cold war, the US Air Force attempted to increase the range of airplanes by carrying fuel in hinged wing panels that supported themselves attached to their wing tips. The initial tests used a piloted light plane to simulate the hinged panels. Soon the scope of the experiments expanded to include towing a pair of jet fighters on the wing tips of a giant bomber. Photo sources: Bud Anderson, Air Force, General Dynamics, Lockheed-Martin:

Douglas C-47A 42-23918 and Culver Q-14B 44-68334
Project Tip-Tow: Boeing EB-29A 44-62093 and Republic EF-84D Thunderjets 48-0641 and 48-0661
Project Long Tom: Beechcraft XL-23C
Project Tom-Tom: Convair JRB-36F 49-2707 and Republic RF-84F Thunderflashes 51-1848 and 51-1849

Put a copy of the Wing Ttip Coupling: 2013 calendar in your Lulu.com shopping cart for $16.95.

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