Franklin O-805
# Franklin O-805

The Franklin O-805 (company designation 12AC) was an American air-cooled aircraft piston engine, designed in the mid-1940s and was to be used in radio-controlled pilotless drones that were to be guided from an accompanying control plane. Due to project requirement changes and cancellations the engine was not produced.

A smaller displacement 12-cylinder Franklin engine of 1941 was known as the O-595 or 12AC-596.

## Variants

### O-805

**12AC-806**


    450 hp (336 kW)0

**12ACG-806 (XO-805-1)**


    456 hp (340 kW) at 3,200 rpm, geared to 0.632:1.

**12ACGSA-806 (XO-805-3 and O-805-5)**


    500 hp (373 kW) at 3,200 rpm, supercharged and geared to 0.632:1 (XO-805-3), or to 0.587:1 (O-805-5).

### O-595

**12AC-596**


    300 hp (224 kW) at 2,600 rpm

**12ACG-596**


    350 hp (261 kW) at 3,500 rpm

## Applications (intended)

* Interstate XBQ-5
* Interstate XTD2R-1

## Survivors

* There is an O-805-2 on display at the New England Air Museum, Bradley International Airport, Windsor Locks, CT
* One surfaced and was sold privately in August, 2016, on eBay for US$8500.

## Specifications (12ACGSA-806/XO-805-3)

### General characteristics

* Type: 12-cylinder air-cooled horizontally opposed aircraft piston engine
* Bore: 4.625 in (117.5 mm)
* Stroke: 4.0 in (101.6 mm)
* Displacement: 806.4 cu in (13.2 L)

### Components

* Valvetrain: OHV
* Cooling system: Air-cooled
* Reduction gear: 0.632

### Performance

* Power output: 500 hp (373 kW) at 3,200 rpm
