Grob G115 Tutor

The Grob G115 is an all-composite, two-seat, side-by-side, low-wing, fixed-gear trainer designed and built by Grob Aircraft SE (formerly Burkhart Grob Luft- und Raumfahrt) in Tussenhausen-Mattsies, Germany. First flown in November 1985 and FAA-certified in 1987, the G115 leveraged Grob's glider-heritage composite expertise to create one of the first all-GRP (glass-reinforced plastic) certified powered trainers in the world. Its sleek lines, bubble canopy, and low-wing layout made it feel more like a stepping-stone to fast-touring aircraft than the Cessna 150/172 it competed against.

The airframe's defining moment came when the G115E variant was selected by the UK Ministry of Defence as the Tutor T.1, replacing the Scottish Aviation Bulldog for Elementary Flight Training across the RAF's University Air Squadrons, Air Experience Flights, and as an initial pilot-screening type. 99 airframes were delivered to the RAF beginning in 1999 under a contract operated by VT Aerospace (later Babcock). The Egyptian Air Force took 74, the Indonesian Air Force, Jordan, Bangladesh, and others followed. Civilian G115s remain popular with European flight schools and a small but loyal US owner base — a few dozen N-registered aircraft, mostly G115C variants that arrived in the early-to-mid 1990s. The retirement of the RAF Tutor fleet (beginning mid-2020s) is gradually releasing low-time, well-maintained G115Es back onto the civilian market, which is slowly reshaping the used-price landscape.

The G115EG designation refers to a ground-school and glass-cockpit enhancement package offered on late-build airframes; mechanically identical to the G115E.

Book cruise for the G115E at 75% power is 124 KTAS, but operators report realistic 115-118 KTAS at 8.5-9.5 gph is typical when flown warm-day with two pilots and fuel. The composite airframe is very clean — glide ratio is excellent (around 11:1), making engine-out training feel deceptively benign compared to the Bulldog or PA-28 it replaced.

The 180 hp AEIO-360 gives the G115E real climb performance (1,000+ fpm at gross) and makes it happy at density altitudes that would hobble an O-235-powered 150. However, the earlier 115 hp G115/G115A variants are noticeably underpowered in warm weather and should not be confused with the Tutor-spec airplane. The bubble canopy gets hot in summer — G115 cockpits run notably warmer than a high-wing Cessna — and the low-wing layout means no natural shade on the ramp.

The airframe is stressed for +6/-3g in the aerobatic variants (C2, D, D2, E). Control harmony is often described as closer to a Zlin or Extra than a Cessna, with light, crisp ailerons and a positive, honest stall.

With 32 gallons usable (192 lbs of fuel) and a 706 lb useful load on the G115E:

• Full fuel + 2 pilots (180 lbs each): 706 - 192 - 360 = -46 lbs. You are over gross with two FAA-standard pilots and full fuel. Realistic loading is full fuel + one 180 lb pilot + 150 lb passenger, or two 180 lb pilots with 26 gallons (157 lbs) of fuel.
• Two pilots + reduced fuel (20 gal = 120 lbs): 706 - 120 - 360 = 226 lbs of baggage margin, but baggage locker is physically limited to ~40 lbs.
• Realistic XC scenario: Two 180 lb pilots, 26 gallons fuel (2:30 endurance with 45-min reserve), 20 lbs of baggage — roughly 275 NM practical leg.

The G115 is a training and fun-flying airplane first; cross-country utility is a real but constrained secondary mission. Unlike a PA-28-161 where full-fuel/two-pilot scenarios work within CG, the G115's payload envelope requires more careful planning — and the 32 gallon fuel capacity is modest for a 180 hp airplane, limiting practical range to ~450-500 NM with reserves.

Flight Training (9/10): This is the G115's reason for existing. The RAF chose it over a field of modern competitors for ab-initio training, and it excels at the role — honest handling, forgiving stall, robust composite airframe, side-by-side seating with excellent visibility, and (in 180 hp trim) enough performance for unusual-attitude recovery and basic aerobatic instruction. See flight-training.

Local Fun Flying (8/10): Great canopy, aerobatic capability on C2/D/E variants, and cruise performance that beats a 172 make this a genuinely fun airplane for the Sunday-morning sightseeing and airshow-adjacent pilot. See local-fun-flying.

Aerobatics (7/10): The G115D/D2/E are certified for +6/-3g and used routinely by the RAF and aero clubs for basic aerobatic training (loops, rolls, spins, stall turns, basic competition figures to Sportsman level). It is not an Extra 300 or Pitts — the 180 hp pulling a 2,183 lb airframe means vertical penetration is limited and it won't snap or tumble like dedicated unlimited machines. Think "aerobatic trainer," not "competition mount." See aerobatics.

Cross-Country (4/10): Two seats, 32 gallons, and 621 NM book range (closer to 480 NM with reserves and realistic cruise) limit this to short-to-medium XC missions. Comfortable cockpit and IFR-capable avionics help, but payload is tight.

Business Travel (2/10): Two seats and limited baggage rule this out for most business use.

Backcountry (1/10): Fixed gear but with small tires, a low wing, low ground clearance, and a composite airframe with no STCs for tundra tires or brush flying. Avoid.

Cargo Hauling (1/10): 706 lb useful load with two full-size pilots and fuel leaves almost nothing for baggage.

Surveying (3/10): Low-wing view is poor for survey, endurance is modest, and the aircraft was never adapted for camera ports.

Entry tier ($85k-$120k, older G115A/B/C civilian): Steam-gauge six-pack, single nav/com (KX155), transponder, basic intercom. VFR-only or marginal IFR. European-spec avionics may need US replacement.

Mid tier ($120k-$170k, G115C/D with upgrades or low-time Tutor retirees): Garmin GNS 430W or GTN 650, second com, ADS-B Out (GTX 335 or similar), digital engine monitor, upgraded intercom. Solid IFR trainer.

High tier ($170k-$220k, late G115E/EG or refurbished): Garmin G500 TXi or dual G5 with GTN 650Xi, GFC 500 autopilot, ADS-B In/Out, engine data to the PFD. RAF Tutor refurbishments sometimes retain the MoD-spec Bendix/King KLN 94 and KMD 850 MFD but are being modernized to Garmin. See avionics-pricing.

The G115 panel is relatively small — fitting a full G3X Touch dual-screen retrofit is possible but requires care with composite panel bonding, and Grob Aircraft SE approval is effectively required to maintain European EASA certification, adding paperwork overhead compared to a metal-airframe Cessna.

The G115 has a sparse STC ecosystem compared to legacy metal trainers:

• Garmin GTN/G5/G3X retrofits — typically via field approval (FAA) or EASA Minor Change; installations common on civilian G115C and ex-military Tutors.
• ADS-B Out upgrades — required for US N-registered aircraft; Garmin GTX 335/345 and uAvionix tailBeacon approved.
• LED nav/landing/strobe lighting — Whelen and AeroLEDs installations common.
• MoD-to-civilian conversion package (Grob Aircraft SE, for ex-RAF Tutors) — removes military-specific equipment, re-certifies to standard civil configuration, updates manuals.

There is no STC for higher gross weight, VGs, STOL kits, floats, or tundra tires — the composite airframe and its European certification basis make aftermarket mods far less common than for a Cessna or Piper.

Parts availability: fair. Grob Aircraft SE (Tussenhausen-Mattsies, Germany) remains the OEM and actively supports the fleet, providing IPCs, AMMs, AFMs, and service bulletins through productsupport@grob-aircraft.com. Airframe-specific parts (composite panels, canopy parts, control surfaces) must come from Germany, which means 4-8 week lead times and euro-denominated pricing. Engine, prop, brakes (RAPCO PMA parts now available), tires, and standard avionics are straightforward.

Mechanic familiarity: specialist. Outside of former military operator bases and a handful of US shops with ex-RAF experience, finding an A&P who has worked on a composite Grob is difficult. Composite repair requires specific training and approved materials; a typical general-aviation A&P will be reluctant to sign off on anything beyond routine inspection. Owner communities (Grob Owners Group, European clubs) maintain lists of qualified shops.

Typical annual cost: $13,000-$16,000 for an owner-operated G115E flown 100 hours/year, excluding engine reserve. Annuals run $3,000-$5,000 with no squawks, more with any composite skin work. Engine reserve at $32,000 / 2,000 hrs = ~$16/hr.

Expensive items: Canopy replacement ($15-20k), composite repair after hail or hangar rash, propeller overhaul (MT composite prop ~$5,000), landing gear leg replacement. See maintenance-ecosystem.

Grob G115 values are driven by variant, engine time, aerobatic capability, and whether the airframe is civilian-origin or ex-military Tutor:

• Engine time (AEIO-360 at 2,000 TBO): runout costs ~$32,000 overhaul plus accessories. Value swings $25-30k mid-TBO to fresh.
• Variant premium: G115E/EG commands 30-50% over G115C for comparable panels due to stronger airframe, 180 hp, and aerobatic rating.
• Ex-military Tutors entering the civil market are typically well-maintained with comprehensive records but require the Grob SE civilianization package ($15-25k) and sometimes panel modernization.
• IFR avionics package adds $15-40k depending on tier.
• Gelcoat and paint condition matters more on composite airframes than metal — a mid-life repaint on a composite is $15-25k with proper primer.

Typical price tiers:

• $85-120k: Older G115A/B, higher-time engine, steam gauges, VFR
• $120-160k: G115C/C2, mid-time engine, basic IFR
• $160-200k: G115D or low-time G115E (civilian or recently released Tutor), modern GPS panel
• $200-220k+: Late-build G115EG or fully refurbished Tutor with glass panel

See valuation-methodology for engine-time and avionics adjustment formulas.

• Rudder hinge and control surface inspection ADs — EASA/FAA issued recurring inspections on control surface bonding and hinge integrity on several G115 variants; compliance is documented in the logbook and checked at annual.
• Fuel system ADs (2022, FAA) — addressed fuel selector valve wear on G115EG airplanes.
• Canopy latch and frame corrosion inspections — composite-to-metal interface at the canopy frame is a known wear point; pre-buy must include careful canopy inspection.
• Landing gear leg attachment bolts — periodic torque checks; any hard landing should trigger a detailed inspection of the composite gear leg attachments.
• Seatbelt attach points — composite airframes with +6g ratings have strict inspection intervals on harness hardpoints.

Pre-buy red flags: Hail damage (composite repair is expensive and non-obvious), UV-degraded gelcoat (resin crazing and yellowing on top surfaces), improperly repaired delamination, non-Grob-approved paint jobs (wrong primer can degrade composite skin), and any prior hard-landing history. Because there are few G115-experienced A&Ps outside dedicated operators, a pre-buy by a Grob-familiar shop is essential.

The G115 is an unusual case for US insurance underwriters — fixed-gear, trainer category, but composite airframe and a non-mainstream type with limited qualified A&P network. Typical hull premiums run $1,500-$2,200 annually for an owner-flown G115E with 200+ hours, standard PPL + complex (not required) + type-specific transition, on a $150k hull. Underwriters may require:

• 5-10 hours dual with a G115-experienced CFI before solo.
• If aerobatic flying is intended, a separate aerobatic endorsement and (sometimes) an aerobatic hull rider.
• Evidence of recent tailwheel-equivalent control authority training (not required, but underwriters like it).

Because parts lead times can be long, insurers may scrutinize hangar storage more than for a Cessna. See insurance-underwriting.