Piasecki HUP Retriever

what is it?

The Piasecki HUP Retriever or H-25 Army Mule, later UH-25, is a compact single radial engine, twin overlapping tandem rotor utility helicopter developed by the Piasecki Helicopter Corporation of Morton, Pennsylvania. Designed to a United States Navy specification, the helicopter was produced from 1949 to 1954, and was also used by the United States Army and foreign navies. The HUP/H-25 was the first helicopter to be produced with an autopilot and also the first to perform a loop.

🔎How to recognise it: 1 piston engine · 10.7 m main rotor

base stats

• speed 169 km/htop speed
• size 2,767 kgmax take-off weight
• built 339made in total

Bars compare against all aircraft: 3,500 km/h, 20,000 km, 850 seats; size and number built on a log scale up to 640 t (An-225) and 45,000 built (Cessna 172).

fun facts

• 🎂First flew 78 years ago, in 1948.
• 🚗Rotor of 10.7 m: about 2 cars parked nose to tail.

piston: A car-like piston engine turning a propeller: simple and cheap, the classic small plane.

spec sheet

first flight

1948-03

introduced

1949

retired

1964

status

retired

number built

339

role

utility helicopter

makers

Piasecki Helicopter Corporation

engines

1× Continental R-975-46A

length

17.4 m

rotor diameter

10.7 m

height

4 m

max take-off weight

2,767 kg

top speed

169 km/h

cruise speed

129 km/h

range

—

ceiling

3,048 m

Specs are for the version in the Wikipedia article's specification section. Blank means the sources don't say.