FLIGHT TEST: Gobosh 700 - What's in a name?

Washington DC
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When Dave Graham and Tim Baldwin created the Go-big-or-stay-home (Gobosh) Aviation company in 2006 after deciding to enter the factory-built light sport aircraft business, the name was not supposed to stick.

Graham, who previously worked as the UK and Irish dealer for Symphony aircraft, says Baldwin had worked in the technology industry and had a competitor with that name. "When we started this business, we needed an entity to operate from," says Graham, now based in Moline, Illinois.

 
With its winglets and smooth contour, the Gobosh 700 has definite ramp appeal. Picture: John Croft/Flightglobal

"We called it Gobosh with every intention of changing it once we got around to marketing. When the marketing people came to advise on name selection, all three firms said that Gobosh was better than anything they came up with."

After taking a flight in the Gobosh 700, one of two LSAs in the company's product line, it is clear why the marketers were stumped. The two-seater, despite its small size, is a very big aircraft in terms of ramp appeal and performance for the money.

Flight International flew with new private pilot and owner Pete Merski on 11 July in a Gobosh 700 that had been a company demonstrator before Merski purchased it and brought it to Lee airport in Annapolis, Maryland. There he has the distinction of being the first LSA operator at the privately owned public-use airport, a purchase decision that keeps in bathed in attention from pilots who do not recognise the airframe.

 
The canopy must be closed to access the fuel tank for avgas or high-octane fuel. Picture: John Croft, Flightglobal

ALL ALUMINIUM
Based on the Polish-built Aero AT-3, Merski's 700, also known as an AT-4, features all- aluminium semi-monocoque construction, a Rotax 912ULS 100hp (75kW), liquid cooled engine with 2,000h between overhauls and three-blade composite propeller, single Dynon SkyView avionics display with synthetic vision, a Garmin 496 navigator with XM radio and weather as well as a Garmin radio and Mode C transponder.

Owners can get either analogue instruments or Dynon glass cockpits installed. Base price with the Dynon D180 upgraded with the SkyView package is $138,500. Ballistic parachutes are not an option.

I had first noticed N1037K when taxiing my 1970s-vintage aircraft at Lee airport, mistaking the model for a PiperSport, with its sharp red livery and low-wing and large forward-lifting one-piece canopy. What was perplexing were the Gobosh 700's winglets.

Walking up to the aircraft, I noticed the "Gobosh Aviation" stencilled on the cowling, which I promptly wrote down on a cardboard box and looked up that evening on the internet. The aircraft has a ramp appeal that draws such enquiries.

The Gobosh 700 today looks different than the AT-3 Graham initially found when touring Europe in 2006 in search of an LSA he could sell under the Symphony brand in the USA. Graham left Symphony in 2006 and teamed with Baldwin.

"When we got back from that trip, a lot of people called us and wanted us to represent their aircraft," says Graham. "We sat down and figured what should be in that aircraft including a two-year, 400h warranty at a minimum, good documentation, backing by a "good solid company", fit and finish and how you take delivery. The initial list included 15 companies, but further refinement whittled the list down to two companies - Aero in Poland and Aveko in the Czech Republic.

While the original names are still used in Europe, Graham said Gobosh wanted to build its own brand in the USA, and changed the name of the modified Aero AT-3 to the Gobosh 700 and the "tamed down" Aveko VL-3 Sprint to the Gobosh 800, a higher-end model starting at $162,000.

More was required than a name change to meet US Federal Aviation Administration LSA standards on 600kg (1,320lb) maximum gross weight, 45kt (85km/h) no-flap stall speed and 120kt maximum speed.

For the Gobosh 700, Gobosh invested in tooling changes to the AT-3 production line to build AT-4 models with an associated longer wingspan, modified wing profile and spar, winglets and fillets between the wing leading edge and fuselage.

The aircraft comes standard as night-flight capable and is approved for one-turn spins. Gobosh launched the Gobosh 700 at Oshkosh in 2007 and so far has sold 25 aircraft, mostly to flight schools. For the G800, launched at the Sebring show in 2008, five units have been sold to date, primarily to private owners.

Merski and I met on a warm Sunday morning for the demonstration flight. He purchased the aircraft three weeks earlier, shortly after earning his private pilot's licence in an analogue-cockpit Cessna 172. Merski says he considered purchasing a late model, Garmin G1000-equipped Cessna 172, but the Gobosh was $50,000 less for the same speed and similar avionics. Although he wanted a four-seat aircraft, he reasoned that most of his flights resulted in only one other person in the aircraft.

The pre-flight walkaround is fairly standard, but does include the special propeller-turning "burping" procedures necessary to check the oil level in Rotax engines. The Rotax has a 2.4:1 gearing system that allows the core engine to spin at an efficient speed, about 5,000RPM in cruise, while the propeller spins quietly in the neighbourhood of 2,000RPM. Also somewhat unusual is the step of checking the coolant level as most legacy aircraft are air-cooled.

The aircraft also features hinged inspection ports in several locations that allow for quicker annual inspections and a quick look at any pre-flight.

Baggage is stored in two compartments, one lockable, on the deck behind the seats. Total baggage allowance is 30kg. The seats are not adjustable forward and aft or up and down. Merski uses cushions to adjust his position. For my 188cm (6ft 2in) height, no cushions were needed. I found the cockpit roomy enough, and I found I could put my feet behind the rudder pedals for an extended flight for more leg room. Getting into and out of the cockpit required some grunting, more due to my lack of physical fitness than the constraints of the airframe. Access could be an issue however for some pilots and passengers.

Engine start was straightforward, with the addition of a choke for cold starts and an oil heater knob, but without the typical mixture control of most small aircraft, a function the Rotax handles internally. The canopy can be left open for starts and taxiing, and engine start was virtually unnoticeable in terms of noise.

Once the canopy is closed, which can cause the cockpit to heat up quickly on a sunny day, vents on the panel and at the rear of the cockpit provide good air flow, and sliding side canopy vents can be left open during flight. Taxiing the castoring nosewheel with toe brakes and rudder can take some practice, but with only a few hours of practice, pilots like Merski can turn the aircraft around in a very tight space.

PRE-TAKE-OFF CHECK
After waiting for the oil temperature to reach 50°C (122°F) and performing a standard pre-take-off check, Merski added 15° of flaps and we departed Runway 30 at Lee, with light headwinds and 26.5°C temperature. The Gobosh has a lever activated split flap design with 15° (take-off) and 40° (landing) increments.

Static engine speed at full throttle was 5,480RPM and lift-off occurred at around 40kt. Climb rate was 800ft/min at 70kt climb airspeed. Noise was relatively low but visibility out of the large unobstructed canopy was immense. A good dose of right rudder is required to counteract P-factor at full power as there is no offset engine cant provided in Merski's early version. New models are canted.

En route to Cambridge airport, 65km (35nm) to the east, we performed a series of steep turns and stalls, both power-on and power-off. The control stick feels very natural, with heavy roll control forces that make for very stable turns with little rudder input needed to centre the digital version of the inclinometer.

With a 30° bank, the aircraft could be flown hands-off with only 100ft or so loss of altitude in a 360° turn. Conversely, the pitch control is very light, making for a crisp vertical response. By the same token, landings required some restraint in stick motion to avoid pilot-induced oscillations. The aircraft was very solid and stable in all phases of flight, including the stall series, with no tendency to drop a wing. We cruised at 2,800ft altitude and 5,280RPM, yielding 115kt indicated airspeed.

In the pattern at Cambridge, Merski throttled back to idle speed abeam the touchdown location on downwind leg, pulled the carburettor heat knob on and flipped the auxiliary fuel pump on. On base leg, Merski pulled in 15° of flaps holding 70kt airspeed.

The Gobosh has a very sensitive trim wheel located between the seats, next to the flap lever, requiring small adjustments only. Using 60kt and full flaps worked well on final, bleeding off excess speed by pitching up slightly over the threshold.

Stall speed with full flaps was roughly 36kt at our weight. Merski says maximum crosswind capability for the Gobosh is 11.7kt, a level that was not an issue on our flight.

Topping the single fuel tank ahead of the cockpit after our 1.5h flight (Hobbs meter) required 19.3 litres (5.1USgal), adding confidence to Gobosh's claims of an average fuel burn of about 15 litres/h.