Kellett UC-48 utility autogyro

Kellett RU-1 utility autogyro

The US Army Air Force was impressed with the performance of the Fokker A.III but were not interested in using an autogyro in a purely offensive role. The Army asked the Kellett Autogyro Corportation to build a utuliy autogyro with similar size and performance to the Fokker A.III.

The resulting autogyro could be configured to carry seven normal passengers (the standard transport configuration), nine cramped passengers (as listed, for short distance raids by slightly undersize airborne squads equipped with minimal gear) or cargo (36 VSP/1.1 tons). The RU-1 (Rotor, Utility) could also be used as an air ambulance, carrying four stretcher patients and no medics or three stretchers and two medics (in either case, the MGs are removed; the gunner is sometimes retained to act as a n orderly). Very early models were specific to each role, but eventually the RU-1E appeared which could be rigured in about half an hour for any of these uses.

Crew consists of two: pilot and observer/gunner. The RU-1 uses 25.7 gallons of aviation fuel per hour.

Subassemblies: Huge Helicopter Chassis +3, Rotors -1, three fixed Wheels +1
P&P: 571 kW HP gasoline engine w/571-kW prop, 75 gallon standard tanks [Body]
Occ: 2 CS, 9 PS Cargo: 0.

Armor
Body: 2/2C
Rotors: 3/10
Wheels: 3/5

Weaponry
2*Aircraft LMG/Browning M-2 [Body:B] (500 each)

Equipment
Body: Long range radio receiver and transmitter, navigational instruments.

Statistics

Size: 60'x50'x12' Payload: 1.37 tons Lwt: 3.32 tons

Volume: 400
Maint.: 65 hours Price: $9,400

HT: 12
HP: 360 [body], 100 [each rotor], 10 [each wheel]

aSpeed: 143
aAccel: 5
aDecel: 8
aMR: 2
aSR: 1
Stall: 27 mph

Take-off roll (loaded): 28 yards. Landing roll (loaded): 9 yards
Take-off roll (no caro/passengers, max fuel): 16 yards. Landing roll (empty, 10% fuel): 5 yards

Design Notes
To better match historical autogyros, rotor area was raised to the 1.75 power in stall calculations and 1.5 power in speed calculations. Takeoff was divided by 3 and landing distances by 10.

Variants
It was realized that the low speed of the RU-1 would be an advantage in a ground attack role (designated the RA-1). Small (Recon Plane) wings were added, with four .30-cal Browning M-2's (750 rpg) and hardpoints for two 250 lb and four 100 -lb bombs (these were later replaced by 4.5"and 5" rockets). Two staggered beam gunners (port and starboard) were added, arch with an LMG and 500 rounds of ammo. A pair of wings cost $1,800 and weighed 440 lbs unloaded (ammo and ordnance are 1,150 lbs). This proved to be effective when not opposed by enemy fighters. While initial production models had the wings fixed, a kit was issued tht allowed the wings to be added or removed at a workshop in about an hour.The RU-1F was the same as the -E but with provisions to mount these wings. although this version lacked the beam guns (and their gunners). For some missions, the two 250-lb hardpoints are unloaded and four commandos are carried, to perform raids after the RU-1 softened up the target with bombs and MG fire.

The Navy ordered a variant of the gunship for use as an ASW platform. The six hardpoints were replaced by ywo, each rated for a singe 350-lb depth charge. The beam guns were removed but the two gunners were retained as observers. Folding rotors were added. These were generally operated from escort carriers (issued at two per ship) and proved quite useful.

Size: 60'x50'x12'	Payload: 1.37 tons	Lwt: 3.32 tons
Volume: 400	Maint.: 65 hours	Price: $9,400