Packard 1A-2500

The Packard 1A-2500 is an American 12 cylinder liquid-cooled aircraft engine designed in 1924.^[1] Of the five variants produced the 3A-2500 was the most numerous.

Applications

• Boeing TB
• Heinkel HE 8
• Martin T3M
• Naval Aircraft Factory PN
• Huff-Daland LB-1

The marine version of this engine was used in most PT boats as the 3M/4M/5M-2500.

Variants

1A-2500

1924, 800 hp. Six built.

2A-2500

1925, 800 hp. 75 built.

3A-2500

1926, Geared propeller drive option, 800 hp. 175 built.

4A-2500

1927, fitted with a supercharger, 900 hp. One built.

5A-2500

1930, experimental use only, 1500 hp. One built.

3M-2500

marine version

4M-2500

marine version

5M-2500

marine version

Engines on display

• A Packard 3A-2500 is on display at the National Museum of the United States Air Force.

Specifications (1A-2500)

Data from Aircraft Engine Historical Society^[2] and Race With the Wind By Birch Matthews^{[citation needed]}

General characteristics

• Type: 12-cylinder V engine
• Bore: 6 ³⁄₈ in (160 mm)
• Stroke: 6 ¹⁄₂ in (170 mm)
• Displacement: 2,490 cu in (40.8 L)
• Dry weight: 1,120 lb (510 kg)

Components

• Valvetrain: Four valves per cylinder, overhead camshaft
• Fuel type: Petrol
• Cooling system: Liquid-cooled

Performance

• Power output: 850 hp (630 kW) at 2,500 rpm
• Specific power: 0.33 hp/in³ (15.2 kW/L)
• Power-to-weight ratio: 0.76 hp/lb (1.25 kW/kg)

See also

• Packard 1A-1500

• Fairmile D motor torpedo boat

Comparable engines

• BMW VI
• Mikulin AM-34
• Rolls-Royce Buzzard

Related lists

• List of aircraft engines

References

Notes

Bibliography

External links

Wikimedia Commons has media related to Packard 3A-2500.

• National Museum of the USAF - 3A-2500 factsheet