Maxair Drifter

Single-seat single-engined high-wing monoplane with conventional three-axis control. Wing has unswept leading and trailing edges, and constant chord; conventional tail. Pitch control by elevator on tail; yaw control by fin-mounted rudder; roll control by full-span ailerons; control inputs through stick for pitch/roll and pedals for yaw. Wing braced from above by kingpost and cables, from below by cables; wing profile; double -surface. Undercarriage has three wheels in tail-dragger formation; suspension on all wheels (type NC). Push-right go-right tail-wheel steering connected to yaw control. Optional brakes on main wheels. Aluminium tube framework, without pod. Engine mounted at wing height driving pusher prop-eller. Dacron wing covering.

The Drifter started life as a modified Hummer, the brainchild of the late Klaus Hill. Maxair Sports dealer Roy Pinner built the first Drifter from a Hummer kit, with some notable design changes. On the Drifter, in place of the V-tail empennage, Pinner built a con-ventional cruciform tail, sporting a regular set of stabilizing surfaces — ver-tical and horizontal. Along with the stabilizing surfaces Pinner constructed a rudder and elevator. Maxair also added bent sheet alumi-num to strengthen the fuselage boom. New landing gear built of springy 4130 chrome-moly steel replaced Hummer’s complex aluminum-tube gear. The wing utilizes a flatter profile, sporting a batten-braced lower surface with some curvature, enabling the craft to slice through the air with less effort. And less effort required means that the Drifter flies faster on the same power as Hummer, even though both sport approximately the same wing area, despite Drifter’s higher empty weight.

The Duralumin and Dac-ron Drifter made its first public appearance as a prototype at Oshkosh in 1982, where it was on static display only, since the aircraft had not at that time completed its flight test programme. The design is by Roy Pinner, marketing director of Maxair Sports, who conceived the Drifter as an improved version of the Hummer from the same company, with a remodelled structure and a conventional tail in place of the characteristic V-tail, as designed by Klaus Hill.

The Drifter has been on sale since May 1983, Maxair Sports differentiating the new model from the Hummer, which is still in production, by emphasising its sprung sus-pension on the main undercarriage and its increased track, which allows more rough-terrain use. It also points out that the tail has become conventional, with large control surfaces, and that the ailerons are now full span. The improved control authority of the Drifter gives better cross-wind capabilities and its performance has been increased by the 38.5 hp delivered by its twin-cylinder in-line Kawasaki TA440A engine. Priced in 1983 at US$5500.

The XP 503 was first introduced at Oshkosh in 1983. A two-seat high wing microlight powered by a pusher 48 hp Rotax 503. Max speed is 63 mph.

By 1984 600 Drifters had flown.

Its cable-braced wing and aluminum fuselage tube resulted in a rigid design that was soon expanded to include a two-seat trainer version and a short-wing, overpowered single-seat hot rod that was well outside ultralight limits. Some Drifters were equipped with monohull or dual floats.

Maxair declared bankruptcy in 1991, and the Drifter project was picked up by Phil Lockwood, who had worked for Maxair. Lockwood Aviation has reintroduced the design. When powered by the 582 Rotax engine the craft will climb out at 900 feet a minute cruise a 70 m.p.h. and stall in the 38/40 m.p.h. range.

Drifter
Engine: Kawasaki TA440A, 38.5 hp at 6000 rpm.
Propeller diameter and pitch 58 x 36 inch, 1.47 x 0.91 m.
V-belt reduction, ratio 2.25/1.
Max static thrust 230 lb, 104kg.
Power per unit area 3.94 hp/sq.ft, 2.7 hp/sq.m.
Fuel capacity 5.0 US gal, 4.2 Imp gal, 18.9 litre.
Length overall 19.0 ft, 5.79 m.
Height overall 7.6ft, 2.32m.
Wing span 30.0ft, 9.14m.
Constant chord 5.0ft, 1.52m.
Dihedral 4 deg
Sweepback 0 deg
Tailplane span 7.4 ft, 2.23 m.
Fin height 6.0ft, 1.83m.
Total wing area 152 sq.ft, 14.1 sq.m.
Fin area 15.0 sq.ft, 1.39 sq.m.
Tailplane area 26.0 sq.ft, 2.41 sq.m.
Wing aspect ratio 5.9/1.
Wheel track 6.0 ft, 1.83 m.
Wheel-base 15.6 ft, 4.72 m.
Tailwheel diameter over-all 4 inch, 10 cm.
Main wheels diameter overall 12 inch, 30cm.
Empty weight 233 lb, 106kg.
Max take-off weight 505 lb 229 kg.
Payload 272 lb, 123kg.
Max wing loading 3.32 lb/sq.ft, 16.2 kg/sq.m.
Max power loading 13.1 lb/hp, 5.9kg/hp.
Load factors +6.0, -3.0 design.
Max level speed 63 mph, 101 kph.
Never exceed speed 63 mph, 101 kph.
Max cruising speed 60 mph, 97 kph.
Economic cruising speed 50mph, 80kph.
Stalling speed 25 mph, 40 kph.
Max climb rate at sea level 1100 ft/min, 5.6 m/s.
Min sink rate 300 ft/min at 40 mph, 1.5 m/s at 64 kph.
Best glide ratio with power off 9/1 at 42 mph, 68kph.
Take-off distance 100ft, 30 m.
Land-ing distance 100 ft, 30 m.
Range at average cruising speed 150 mile, 241 km.

Drifter DR 277
Empty wt. lbs: 252
Max wt. lbs: 500
Wing span: 30 ft
Wing area sq.ft.: 152
Height: 8’4”.
Length: 19’
Fuel cap: 5 USG.
Construction: Aluminium, Dacron.
Wing loading lbs/sq.ft: 2.9
Power  loading lbs/hp: 17.86
Engine: Rotax 277 (268cc) 28 hp.
Drive: 2.25-1.
Prop: 56 in.
Static thrust: 230 lbs.
Max speed mph: 63
Cruise mph: 50
Stall mph: 26
Vne mph: 75
Climb rate: 600 fpm @ 40 mph.
Design limits: +6, -3.3g.
Glide ratio: 8.2-1.
Seats: 1.

Drifter DR 532
Empty wt. lbs: 310
Max wt. lbs: 570
Wing span: 23ft
Wing area sq.ft.: 117
Wing loading lbs/sq.ft: 4.8
Power loading lbs/hp: 8.91
Engine: Rotax 532
Max speed mph: 95
Cruise mph: 65
Stall mph: 34
Vne mph: 100.

Drifter MU 532
Empty wt. lbs: 360
Max wt. lbs: 900
Wing span: 30ft
Wing area sq.ft.: 152
Wing loading lbs/sq.ft: 4.8
Power loading lbs/hp: 14.06
Engine: Rotax 532
Max speed mph: 80
Cruise mph: 60
Stall mph: 35
Vne mph:84
Seats: 2.

Drifter XP 503
Empty wt. lbs: 335
Max wt. lbs: 785
Wing span: 30ft
Wing area sq.ft.: 152
Wing loading lbs/sq.ft: 4.7
Power loading lbs/hp: 15.1
Engine: Rotax 503
Max speed mph: 75
Stall mph: 31
Vne mph: 79
Seats: 2.
Glide ratio: 8: 1
Cruise: 48 knots (46-50 knots)
Take-off: 108 m
Landing: 108 m
Rate of climb: 450 to 600 fpm
Useful load: 204 kg

Drifter DK 440
Empty wt. lbs: 270
Max wt. lbs: 575
Wing span: 30 ft
Wing area sq.ft.: 152
Height: 8’4”
Length: 19’
Fuel cap: 5 USG
Construction: Aluminium, Dacron
Cruise: 45-63 mph
Vmax: 70 mph
ROC: 900 fpm
TO run: 100-200 ft
Ldg roll: 185-285 ft

Tiger Aviation Drifter SB
Top speed: 90 mph
Cruise: 74 mph
Stall: 36 mph
Range: 250 sm
Rate of climb: 600 fpm
Takeoff dist: 350 ft
Landing dist: 350 ft
Engine: Rotax 582, 64 hp
HP range: 64-80
Fuel capacity: 15 USG
Empty weight: 550 lb
Gross weight: 1100 lb
Height: 7 ft
Length: 18.5 ft
Wing span: 30 ft
Wing area: 156 sq.ft
Seats: 2
Landing gear: tailwheel