Maule M-7-235B Super Rocket

The Maule M-series is one of GA's best-kept secrets — a family of high-wing, fabric-covered STOL aircraft that has been in continuous production since 1963 at the Maule factory in Moultrie, Georgia. Designed by B.D. "Belford" Maule, these steel-tube-and-fabric aircraft combine exceptional short-field performance, remarkable load-carrying ability, and surprising cruise speed into a versatile package available with tailwheel or tricycle gear, and on wheels, floats, or skis.

The M-series spans four major model groups: M-4 (1963-1983, 145-220HP), M-5 (1973-1980s, 210-235HP), M-6 Super Rocket (limited production, extended wingspan), and M-7 (1984-present, 160-420HP) — all certificated on the single TCDS 3A23, currently at Revision 34. Total production across all variants exceeds 2,300 aircraft. The M-7-235B Super Rocket is the current production mainstay and this page's chosen representative variant.

Maule aircraft are hand-built in small numbers — annual production is typically 20-40 aircraft. This artisanal approach means long lead times for new aircraft but also means each airplane receives individual attention. The factory is known for accommodating custom configurations.

The M-7 can seat five (two front, three rear bench) and is available in an astonishing array of configurations: tailwheel (M-7), tricycle gear (MT-7), on floats, on amphibious floats, on skis, and even as a turboprop (M-7-420 Starcraft, Allison 250-B17C, 420 shp). The Starcraft is a genuinely different airplane by this catalogue's own splitting rule — different engine class (turboprop vs. piston) is a Step 1 hard split, no exceptions — and it is not a hypothetical STC: the M-7-420A and M-7-420AC appear on TCDS 3A23 itself as certificated models, not as an aftermarket conversion. It is not split out to its own page this session; it remains a Variants-table entry only, flagged here as a known gap rather than fixed, because fully sourcing it (its own certificate section, its own performance data) was outside this session's scope.

The M-7-235B cruises at approximately 137 KTAS at 75% power, "optimal altitude" — Maule's own factory page gives no specific altitude figure, so cruise_altitude_ft is left blank rather than guessed.

Fuel burn, range, takeoff/landing distance, rate of climb, service ceiling and stall speed are genuine gaps, not oversights, and this catalogue's own certification-basis rule (rule 25) predicted exactly this shape of gap: a Part 23/CAR3 TCDS gives no performance data at all, and Maule's short-form AFM (1993, FAA-approved, 31 pages) appears not to carry the GAMA-style performance charts that make a Cessna or Piper POH so rich — no cruise table, no takeoff/landing chart, and no stall-speed table were visible in the accessible preview. The factory's own marketing page publishes figures for all of these, but every one of them (with the sole exceptions of cruise speed and the empty-weight/useful-load pair) is explicitly qualified "light weight" — one pilot, 22 gallons of fuel — and the page's own footer says "Do Not Use for Flight Planning." Storing those numbers in fields this catalogue defines as gross-weight, standard-day figures would be a unit-of-condition error in the same family as landing distance quoted as ground roll, or CAS stored as KIAS — a real number, attached to the wrong condition. AOPA's own 1998 fact sheet independently confirms the gap: its spec table for this engine family lists "Stall Speed Clean: Unknown," "Climb Best Rate: Unknown," "Service Ceiling: Unknown," and "Avg. Fuel Burn at 75% power: Unknown" — evidence that this is a thinly documented type, not a research shortfall this session.

A buyer should still expect, informally, something like the factory's own light-weight figures scaled up: roughly 40-50 KIAS stall at gross (versus the factory's stated 35 kt light), takeoff and landing distances meaningfully longer than the factory's 250-600 ft figures, and a service ceiling somewhat below the factory's stated 15,000 ft. None of that is precise enough to store as a cited number.

MOSAIC eligibility (mosaic_eligible: false) was left unchanged from the prior pass and may be wrong. A rough scaling estimate (stall scales with the square root of weight; light weight is roughly 1,900 lb against a 2,500 lb gross) suggests a gross-weight Vs1 around 40 KIAS — comfortably under MOSAIC's 59 KCAS Sport Pilot threshold — which would make this airplane MOSAIC-eligible. That estimate is not a sourced figure and is not used to flip the field; it is recorded here so a future pass with an actual AFM stall table can settle it.

The Maule's defining characteristic is its STOL performance — massive flaps (60° deflection available) — though the specific published stall speeds are, per above, a light-weight figure rather than the gross-weight one this catalogue would normally store.

The fabric-covered steel tube construction makes the Maule uniquely tough for backcountry operations — minor fabric damage from branches or gravel is far cheaper to repair than aluminum or composite damage. The high-wing configuration provides excellent ground clearance and protects wing surfaces from debris.

M-7-235B Super Rocket (O-540-B4B5/IO-540-W1A5, 235HP, 40 gal usable standard fuel, 2,500 lb gross):

Useful load (895 lb, corrected from an unsourced 951 lb in the prior pass) is still excellent for a 235HP single — comparable to a Cessna 182. Two adults with full fuel have outstanding payload capacity for backcountry cargo operations. Range is not stated here — see Performance Notes for why the source figures cannot be combined into one.

• Flight Training (4): The MX-7-180 and MXT-7-180 are used for tailwheel and backcountry training. Not ideal for primary training due to cost, tailwheel complexity (tailwheel variants), and limited availability. The tricycle MXT variants are more accessible for training.
• Backcountry (9): This is the Maule's primary mission. Exceptional STOL performance, high useful load, tough construction, high wing with good clearance, and availability on floats/skis/tundra tires. One of the few certified alternatives to the PA-18 Super Cub for serious backcountry work, with more cabin space and load capacity.
• Business Travel (3): ~137 KTAS is moderate. Five seats available but cabin comfort is basic. Fabric-covered aircraft don't project the same image as a Bonanza or SR22.
• Aerobatics (1): Not aerobatic certified (Normal category only).
• Cross-Country (5): Adequate cruise speed; the high wing provides a stable ride in turbulence. No sourced range figure this session — see Performance Notes.
• Cargo Hauling (7): Excellent. The M-7's 895 lbs useful load, rear cargo door, and five-seat capacity make it a genuine utility hauler. The high wing and wide cabin accommodate oversized cargo. Popular with bush operators for supply runs.
• Local Fun Flying (7): The Maule is a blast to fly — excellent visibility from the high wing, responsive controls, and the ability to access tiny strips makes every flight an adventure. The STOL capability means you can explore strips that exclude most other aircraft.
• Surveying (6): High wing provides excellent downward visibility. Good slow-flight characteristics for low-altitude survey work.

• Typical older Maule (M-4/M-5): Basic VFR panel with standard six-pack, single nav/com. Many older Maules are VFR-only backcountry machines.
• Modern M-7 factory: Maule offers Garmin G3X Touch or G500 TXi as factory options. New-build Maules can have very capable panels.
• Common upgrades ($10,000-$25,000): Garmin G5/GI-275, GTN 650Xi, ADS-B transponder. The panel space accommodates modern glass avionics well.
• IFR: Capable with appropriate avionics. The M-7-235C Orion with fuel injection is particularly well-suited for IFR operations.

The Maule has excellent configuration flexibility from the factory:

• Float installations: Edo and Wipaire floats available. Amphibious floats from Wipaire (Wipline 2100/2350). Float-equipped Maules are popular in Alaska and Canada.
• Ski installations: Federal and Airglas wheel-skis. Essential for winter backcountry operations.
• Tundra tires: 29" and 31" tundra tires for soft/unimproved surfaces. Most backcountry Maules run tundra tires.
• Engine upgrades: Various O-540 and IO-540 options through the factory. The M-7-260C with IO-540-V4A5 is the top piston performer.
• Turboprop: The M-7-420 Starcraft (Allison 250-B17C, 420 shp) — a certificated model on TCDS 3A23, not an aftermarket STC. See Overview.
• Extended range tanks: TCDS 3A23 Section XXVI itself lists an optional 47.6 gal (43 gal usable) tank; NOTE 16 records a further 47.6 gal option for the M-5 series with Modification Kit No. 15.
• Vortex generators: Available for further STOL improvement.

• Annual inspection: $1,500-$3,000. Fabric inspection adds time beyond metal airframe annuals.
• Engine overhaul: $52,000 for O-540 at 2,000-hour TBO (reference/engine-overhaul-pricing.md).
• Fabric re-cover: $15,000-$25,000 every 15-25 years. The single largest maintenance expense unique to fabric aircraft. Budget $1,000/year for fabric reserves.
• Parts availability: Good. Maule Air Inc. in Moultrie, Georgia is still in business and maintains parts support for all models. Steel tube components can be fabricated by qualified welders.
• Mechanic familiarity: Specialist. Fabric-covered steel tube aircraft require mechanics experienced with fabric inspection, repair, and re-covering. Not every A&P shop does fabric work.
• Annual all-in cost: $15,000-$22,000 at 100 hours/year.
• Operating cost: $100-$140/hour all-in.

• M-4 series (1963-1983): $60,000-$130,000. Older but functional; Franklin-engine models less desirable.
• M-5 series (1973-1980s): $80,000-$160,000. Improved STOL performance over M-4.
• M-7 MX-7-180 (160-180HP): $90,000-$180,000. Economy models; good trainers.
• M-7-235B/C (235HP): $150,000-$300,000. Primary production model; most available.
• M-7-260C (260HP): $200,000-$350,000. Top performer; premium pricing.
• New factory M-7: $300,000-$540,000+ depending on configuration.
• Float-equipped: Add $52,000-$60,000 to landplane values.

This band was not independently re-sourced this session — the primary-document effort went into the certificate and handbook layers. A Vref/Bluebook pass is still owed for this page.

Per Aircraft Valuation Methodology: Configuration is the primary value driver — float-equipped, tundra-tired, Alaska-modified Maules command significant premiums. Fabric condition is critical; recent re-cover adds $15,000-$20,000 to value. Engine time on the O-540 (overhaul at $52,000) is standard. The M-7-235C Orion (fuel-injected) and M-7-260C command premiums over carbureted models.

Key ADs:

• Wing lift strut corrosion: Repetitive inspection AD for internal corrosion of wing struts. This is the most significant recurring AD. Struts with wall thickness below 0.020 inches require replacement. The inspection involves removing strut fairings and using ultrasonic testing.
• Elevator control rigging: AD issued after two accidents caused by reversed elevator controls during maintenance. Requires specific rigging verification procedures.
• Rudder cable Nicopress sleeve: AD for improper crimping of rudder cable sleeves. Inspection required to prevent cable slippage.
• Fabric condition: While not an AD per se, fabric covering has a finite life. Ceconite/Poly-Fiber covering typically lasts 15-25 years depending on UV exposure and climate.

Common Problems:

• Fabric deterioration: The most visible maintenance item. Fabric covering degrades with UV exposure. Re-covering costs $15,000-$25,000 and is needed every 15-25 years.
• Tailwheel shimmy: Common on tailwheel variants. Requires proper shimmy damper maintenance.
• Engine cooling: The 235HP O-540 in the tight Maule cowling can run hot. CHT monitoring recommended.
• Brake wear: Tailwheel Maules use differential braking for ground handling, accelerating brake wear.
• Landing gear legs: Spring steel gear legs can develop fatigue cracks at attach points. Inspect carefully at annual.

Per GA Insurance Underwriting:

• Hull insurance: $2,000-$4,000/year. Tailwheel premium applies on tailwheel variants. Float operations increase premiums further.
• Liability: $500-$1,000/year.
• Pilot minimums: Tailwheel endorsement mandatory. 200+ hours total with 50+ hours tailwheel recommended. Float endorsement for amphibian operations.
• Tailwheel premium: Expect 25-50% higher hull rates than equivalent tricycle gear aircraft. Experienced tailwheel pilots (500+ hours, 200+ tailwheel) get significantly better rates.
• Float operations: Additional premium for float flying — typically 15-25% above landplane rates.