Maule M-5 Lunar Rocket

Of tube and fabric construction in the fuselage with metal wings. In essence, the Maule M5 is similar to the M4 but with larger vertical and horizontal tail surfaces and more effective flaps. Apart from the improved STOL capability of the M5, it also possesses a significantly more flexible C of G range.

Belford decided to put the six-cylinder, 235-hp Lycoming into his M-5 because of the engine's reliability. The M-5 is available with a 210-hp engine, but customers have opted for the 235-hp version. The O-540 has a 2,000-hour TBO and has proved remark-ably trouble-free over the years. The only airworthiness directive that has affected the engine was related to its Bendix magne-tos.

The M-5's skeleton is a steel-tube structure, heavily primed against corrosion, since so many Maules end up on floats. With the exception of the aluminum that en-cases the cockpit and the fiberglass engine cowling, the fuselage is covered with a glass-fiber fabric that constitutes a perma-nent skin, never requiring testing for strength. The special high-lift wings are metal-covered, and the wingtips, heavily drooped, are of fiberglass. The rugged main landing gear is mounted on pneumatic shock absorbers; the beefed-up tailwheel is designed to withstand the shock of chuck-holes. There are four doors, one on the left for the pilot and three on the right; the center passenger door and the aft luggage door have no separating post, so that when opened together, they provide a four-foot gap for the loading of bulky cargo. As an option, there is a lightweight rear-folding benchseat. A pilot could fold the seat flat, carry a full load of cargo to a remote village and unfold it on the return flight to carry a full load of passengers.

The interior of the M-5 is well designed, if a bit narrow, and the work is of a high quality, thanks to an elderly lady at the Maule factory who is "a genius in upholstery." Overhead, the ceiling is covered with a thick, heavy-weave fabric, a welcome change from the plastic of most airplanes. The instrument panel is dark, functional metal, and the switches and gauges are grouped intelligently. Overall, the Maule's interior, like its exterior, seems tough, built to withstand the rigors of bush flying.

A total of 63 gallons of usable fuel is carried in four wing tanks; the engine feeds directly from two 20-gallon inboard tanks, which can be refilled in flight, with the additional gas pumped electrically from two 11.5-gallon outboard tanks. So, while a full-fuel payload is about 462 pounds, the pilot can fill only the mains and load 600 pounds of people and cargo into the cabin. The seaplane ver-sion has a gross weight 50 pounds higher, which is more than offset by the weight of the floats. Maule in 1979 was in the process of raising the airplane's gross weight by 200 pounds to 2,500 pounds - a change that would apply retroactively to all M-5s.

The Maule is a workable IFR airplane, and 95 percent of the M-5s go out with full IFR avionics. It cruises well, burning roughly 12 gallons an hour at 65-percent power, which at 8,000 feet gives it a true airspeed of about 134 knots. But other airplanes fly faster on less gas. The Maule's real strength is its short-field ability.

The M-5 was introduced in 1974 and the first M-5 Lunar-Rockets were delivered in 1974 as M-5-21OCs with 210-hp Continental engines. The M-5-220C houses a 220-hp Franklin. These models differ from the earlier M-4s by having four cabin doors for hauling cargo as the “C” in the model number implies; otherwise, the M-5 has a 30% increase in flap area and enlarged tail surfaces to enhance its short-field performance. The 220-hp version was discontinued when the Franklin engine was no longer available, and the M-5-235C was added to the line in 1976 employing a 235-hp Lycoming.

Factory base price was $20,565 in 1975. The 1975 used price range: $13,000 to $16,000 for '70 through '72 models, and $17,000 to $19,500 for '73 through '75 models.

The 1977 M-5 model was fitted with either the 210-hp Continental 10-360-D33A or a 235-hp Lycoming.

The Maule M-5 Rocket, which has been manufactured steadily, if in relatively small numbers, in Moultrie, Ga. since the early sixties, is a STOL airplane designed to fly from short, rough fields. With a stalling speed of only 38 mph, and the ability to takeoff over a 50-ft. obstacle in 550 feet, the Maule is seldom seen on paved runways. Most are at work in Alaska, the American West, and in Latin America. Cruise of the later models is in the 160 + mph class.

Gallery

 
M-5-180
Undercarriage: conv. oleo
Produced: 1979-87
Engine: Lyc O-360, 180 hp
TBO: 2000 hr
Prop: C/S
Wingspan: 30'10"
Wingtip: Droop

M5-180C

M-5-200
Undercarriage: conv. oleo
Produced: 1981-83
Engine: Lyc IO-360, 200 hp
TBO: 2000 hr
Prop: C/S
Wingspan: 30'10"
Wingtip: Droop

M-5-210C Lunar Rocket
Engine: 1 x Continental IO-360-D, 210 hp
TBO: 1500 hr
Prop: McCauley CS
Wingspan: 30'10"
Wingtip: Droop
Seats: 4
Wing loading: 14.57 lb/sq.ft
Pwr loading: 10.95 lb/hp
Gross wt: 2300 lb
Empty wt: 1350 lb
Equipped useful load: 887 lb
Payload max fuel: 509 lb
Range max fuel/75% pwr: 672 nm/4.9 hr
Range max fuel / 55% pwr: 837 nm/ 6.7 hr
Service ceiling: 18,000 ft
Top speed 158 mph
75% cruise: 137 kt
55% cruise: 126 kt
Stall: 49-54 kt
1.3 Vso: 64 kt
ROC: 1250 fpm
Min field length: 600 ft
T/O dist: 400 ft
Ldg dist: 400 ft
Fuel cap: 240/378 lb
Undercarriage: Fixed tail / oleo
Produced: 1974-79

M-5-210TC
Engine: Lyc TO-360 turbo, 210 hp
TBO: 1800 hr
Prop: C/S
Wingspan: 30'10"
Wingtip: Droop
Undercarriage: conv. oleo
Produced: 1979-81

M-5-220C
Undercarriage: conv. oleo
Produced: 1974-75
Engine: Franklin O-350, 220 hp
TBO: 1500 hr
Prop: C/S
Wingspan: 30'10"
Wingtip: Droop

M5-235
Engine: Lycoming O-540-J1A5D, 235 hp
TBO: 2,000 hrs
Prop: two-blade, constant-speed, 84-inch diameter
Length: 27 ft. 7 in
Height: 6 ft. 4 in
Wingspan: 30 ft. 10 in
Wing area: 157 sq. ft
Max ramp weight: 2,300 lb
Max takeoff weight: 2,300 lb
Standard empty weight: 1,400 lb
Max useful load: 900 lb
Max landing weight: 2,300 lb
Wing loading: 14.6 lb/sq.ft
Power loading: 9.8 lb/hp
Max usable fuel: 63 USG/378 lb
Max rate of climb, sea level: 1,300 fpm
Max rate of climb 8,000ft: 800fpm
Max operating altitude: 20,000 ft
Max speed (8,500 ft): 148 kt
Cruise, 65% power at 8,000 ft: 134 kt
Fuel flow at 65% power: 12 USG/hr
Endurance at 65% power, no res: 5 hr
Stalling speed, clean: 54 kt
Stalling speed, flaps down: 49 kt
Turbulent-air penetration speed: 109 kt
Seats: 4

M-5-235C Lunar Rocket
Engine: 1 x Lycoming O-540-J1A5D, 235 hp
TBO: 2000 hr
Prop: McCauley 3 blade, CSU
Wingspan: 30'10"
Wingtip: Droop
Seats: 4
Wing loading: 14.57 lb/sq.ft
Pwr loading: 9.79 lb/hp
Gross wt: 2300 lb
Empty wt: 1400 lb
Equipped useful load: 837 lb
Payload max fuel: 459 lb
Range max fuel/75% pwr: 641 nm/4.3 hr
Range max fuel / 55% pwr: 688 nm/ 5 hr
Service ceiling: 20,000 ft
75% cruise: 149 kt
55% cruise: 139 kt
Stall: 49-54 kt
1.3 Vso: 64 kt
ROC: 1350 fpm
Min field length: 600 ft
Fuel cap: 240/378 lb
Undercarriage: Fixed tail / oleo
Produced: 1976-88

M-5-250C
Undercarriage: conv. oleo
Produced: 1975
Engine: Franklin TO-350, 235 hp
TBO: 1500 hr
Prop: C/S
Wingspan: 30'10"
Wingtip: Droop