1000AIRCRAFTPHOTOS.COM

History Brief, by Johan Visschedijk

February 12, 2004

Airmaster Avalon 680


Lawrence (Larry) Matanski founded in 1980 Airmaster Inc. in Renton, Washington, to produce and market the Avalon 680 amphibian aircraft he was designing. The all-metal aircraft was powered by a single 750 shp Pratt & Whitney PT6A-135 turbine engine mounted atop the wing and cabin, driving a pusher propeller, which rotated between the twin-boom tail. The prototype N767LB flew for the first time in October 1983.

The six-seat cabin was unpressurized; the nose-wheel landing gear was retractable with the main wheels stored into the sponsons. The sponsons were attached to stubs and from these stubs two struts supported the wing where they connected at the twin-booms.

The production model would have a 24 in (0.56 m) fuselage stretch, additional cabin windows, optional pressurization, 62 sq.ft (5.76 sq.m) increase of wing area, sponsons moved 5 in (0.13 m) out, a 4 in (0.10 m) wider rear hull, fuel tanks in the stubs, and larger fins and rudder.

From land the Avalon needed 800 ft (244 m) to get airborne, from water this was 1,200 ft (366 m). Landing run on land was 650 ft (198 m), on water this was 700 ft (213 m). Maximum landing weight was 5,100 lb (2,313 kg), cruise speed was 200 mls (322 km)/h, stall speed 65 mls (105 km)/h.

An twin-engined Avalon Twin Star 800 was developed to be powered by two Allison 250-C20Bs providing a total of 820 shp would drive a single pusher propeller. Also an Avalon Twin Star 1000 and a military A-1200 Guardian have reportedly been designed, but except for the Avalon 680 prototype no further aircraft have flown.

Avalon 680 Larry Matanski Aviation Memorial Photo Tribute

Specifications

Type:

Six-seat amphibian

Engine:

One 750 shp Pratt & Whitney PT6A-135 turbine engine

Span:

44 ft 0 in (13.41 m)

Length:

32 ft 0 in (9.75 m)

Height:

12 ft 6 in (3.81 m)

Wing area:

264 sq.ft (24.53 sq.m)

Empty Wt:

3,300 lb (2,404 kg)

Max T/O Wt:

5,300 lb (1,497 kg)

Max speed:

230 mph (370 km/h) at 16,000 ft (4,877 m)

Max climb:

2,200 ft (671 m)/min

Range:

900 mls (1,448 km)

Models

Avalon 680:

prototype only

Avalon Twin Star 800:

projected 7-seat twin-engined 820 shp version

Avalon Twin Star 1000:

projected 7-seat twin-engined 1,000 shp version

A-1200 Guardian:

projected 1,200 shp military version