M-5 bomb trailer used with M-6/CCKW

[RANGER]

The above picture of the M-6 Bomb Truck with Trailer leads me to this topic.
The Army Air Force requirements were for a trailer to deliver bombs to aircraft. It had to be low and maneuverable to get below the bomb bays of the aircraft. To arrive at the lowest possible height, a drop center rear axle was incorporated, and a castoring front axle with dual front wheels was used. Many have wondered why 750X18" rear tires mounted on 5 hole Budd wheels were used, as the more common 750X20 tires mounted on 6 hole Budd wheel would seem more logical. The answer was that having the lowest possible deck height was the reason. You now know why they used the odd ball 18" wheels.
It was found that the castoring front wheels were a problem on poor roads of primative airfields, an auxiliary spring was then added which allowed more load to be transferred to the pintle hook of the towing vehicle.
Some present day M-5 owners remark about the tow bar being difficult to hook up to their pintle, perhaps the reason for the auxiliary spring is now clear.
Tires for the M-5 appeared to be mostly commercial truck tread, I will have to check the M-5 SNL to see if a NDT is mentioned.

Ain't it refreshing to get off the topic of trucks for a moment?

[RANGER]

During WWII, they were for the most part painted lusterless OD, but post war it appears that they were repainted Chrome Yellow, keeping with the post war USAF starting in 1948. Not too many airfields were subject to enemy attack after WWII and during the Korean conflict.

All of the surplus M-5s I have witnessed being offered during the 50s-60s were yellow.

[Guest]

There are 2 different spring arrangements shown in the manual for the M5, one transverse (earlier) and one longitudinal.

There is a 3rd type of which I have seen 2 identical that I believe may have been a post war mod as there were professionally done having the lifting mechanism/crank assy mounted vertically on the front between the spring and the towing bar. The ones in the manual show some trailers having a hinged cranking assy mounted between the towing bar and the lunette assy. With that the lunette can be raised to attach to the Bomb Truck and then the front of the trailer elevated. I believe only the "lead" trailer in the train of them up to 5 long had this mechanism. I have only seen one in the 6 or so M6 trailers I have seen.

The caster (note spelling) wheels in the front have a damper which resembles 1/2 a disk brake rotor. Many times the connection between this rotor and the caster assy is worn and a little loose, In that case, the damping on the caster wheels will be ineffective and the wheel assy may get violent when towing.

[RANGER]

Shimmy is a result of worn parts, scheduled maintenance per the TM will eliminate the problem. Trailering the M-5 long distances down the turnpike to a show was not envisioned in WWII, although the trailer was designed to be pulled at speeds up to 45 MPH.