Gobosh 800XP: Flying With Composites

I had flown the Gobosh 700 a year or so before, and the new 800XP was touted as a different type of machine. Gobosh has always claimed it builds luxury-sport aircraft, not light-sport aircraft. Indeed, the company's name alludes to "Go big or stay home," a suggestion that the Gobosh 700S and 800XP are a cut above the competition.

These days, that might be tough to verify. The industry has gradually expanded to include 80 manufacturers, all hoping to cash in on the LSA boom that started nearly five years ago when the FAA approved the first few LSA.

Gobosh introduced the 700S in 2007, and the company has now premiered a new model. Both the 700S and the 800XP use the same Rotax 912 engine with 100 hp out front driving a fixed-pitch, three-blade, composite Elprop. The new 912 engine is a relatively high-compression (10.5:1), four-stroke mill that turns 5,800 rpm at redline and uses a 2.43:1 gear to reduce prop rpm to a more civilized 2,400. Max cruise is 5,100 engine rpm for 2,100 revs at the prop. TBO is 1,500 hours.

Aesthetically, the two airplanes look similar, though the 700 features a mackerel scoop beneath the cowling, while the 800 utilizes a smaller scoop with characteristic LoPresti-style cooling vents on either side of the prop. The 800 also has a considerably longer wing.

The 700 is made of all-aluminum construction, but the newer 800 is a composite airplane---not just composites covering an aluminum fuselage and wing, but a totally composite design. In fact, since the engine and prop are essentially the same on both airplanes, you have to conclude that composites alone reduce empty weight from 818 pounds on the 700S to 760 pounds on the 800XP.

That's all the more surprising considering that the 700S uses four feet less wing. You'd expect that to result in a lighter empty weight, but composites are so disproportionately lighter that they easily offset the longer wing.

Gross weight is limited by regulation to 1,320 pounds on both airplanes, so the 800XP benefits with a useful load of 560 pounds. Subtract 29 gallons of fuel, and you're left with 386 paying pounds (two good-sized folks and then some). In contrast, the 700S offers a reduced 18.5 gallons against an empty weight of 818 pounds, so payload is 391 pounds, about the same as the 800XP but with considerably less endurance.

A design from the Kabrt brothers of the Czech Republic, the 800XP represents one of the more aesthetic designs in the industry, partially a function of composites. It's a faired and swept low-wing single with rakish looks, spiffily spatted wheels and a traditional horizontal stabilator. The earlier 700S proved a quick and capable little airplane, so I was curious what could be different about the 800XP (besides the use of composites).

The major change between the 700 and 800 is control response, in spades. The 700 is a nice-handling airplane with no bad habits that's pointed directly at the training market, but the 800 is directed more at the sport-flying buyer. Aileron and elevator response is right now, with practically no slop. Pitch and roll reactions are much quicker than on any other LSA I've flown. Aileron inputs, always the most dynamic, almost seem aerodynamically assisted by aileron shovels (à la Pitts S2C). In fact, the airplane cries for aerobatic certification.

The two aircraft offer fairly comparable performance. With the longer wing, you might expect the 800XP to fly slower, but the opposite is the case. The 800 climbs at 1,050 fpm, and the 700 at 850 fpm. Gobosh lists the 800's cruise spec at 119 knots against the 700's 116 knots.

In fact, both the latter numbers are under perfect conditions with all vents closed, the CG at the aft limit, the moon in the proper phase and all your biorhythms at their peak. In the normal world, you should see a realistic 112 to 115 knots from the 800 under reasonable conditions. Pilots in less of a hurry may throttle back to 65% and drift along at an easy 105 knots.

Endurance is one area where you might not logically expect big numbers, but the 800XP, with its larger fuel tank, boasts very respectable reach. Fuel consumption with the little 912 Rotax is about 3.8 gph. Round up the book burn to 4 gph, and you have an easy six hours of endurance on the 800XP (31⁄2 hours on the 700S). At a block 110 knots, the 800XP offers 730 nm between restroom breaks---Albuquerque to Houston, Chicago to New Orleans, or St. Louis to Philadelphia.

True, you might not want to sit in any little airplane for that long, but at least you could take some consolation that you'd only burn about $100 worth of avgas on such a trip. Remember, too, that the 700S and 800XP are both approved for mogas, reducing the cost by perhaps another 20%.

Think about that for a minute. You can transport two people over 600 nm for less than $100. No, that doesn't include all the other costs of running an airplane, but even at double the cost, Southwest or JetBlue would be hard-pressed to match it.

The Gobosh's low-speed capability makes landings nearly automatic. Elevator sensitivity at cruise is almost too good, and you might anticipate a tendency to overcontrol pitch during landing. Fortunately, the 800XP has a super-low stall of only 35 knots in the dirty configuration, and that means you can mosey down final as slow as 50 to 55 knots. That's so slow that aerodynamic forces across the control surfaces are extremely low.

Overcontrolling the pitch axis doesn't turn out to be a problem. You can easily ground the airplane in considerably less than 1,000 feet and get back off in roughly the same distance.

It's not necessary to settle for second-class avionics in a Gobosh 800XP. The airplane comes standard with a Garmin 495 (GPS only) in an AirGizmos mount, a Garmin SL 40 COM and a Garmin GTX 327 transponder. There are a number of upgrades, including a step-up to a Garmin 496 and a TruTrak autopilot (a desirable option for this capable little plane). A dual-screen Dynon glass panel is standard on the 800XP.

Back in 2005 when the feds approved the light-sport rule, the goal of most manufacturers was to build the type for less than $100,000. That has proven something of an improbable---if not impossible---mission, though some manufacturers are still attempting to bring their products under the $100,000 mark.

Others have accepted the inevitable and are pricing the airplanes at more realistic numbers that may even allow for making a profit. Jack Pelton of Cessna had hoped the new 162 SkyCatcher could be sold for under $100,000, but it appears the price will now be at least $10,000 above that.

The new Gobosh 800XP is priced at $135,900, but Gobosh makes no apologies. This is far from an entry-level airplane. It comes with a ballistic parachute (à la Cirrus), plus a two-year, 400-hour warranty, and Gobosh appears to be in the market for the long run. Gobosh President Tim Baldwin and Vice President Dave Graham are young veterans, having been involved in the Symphony 160 project, and they plan to make their living in this industry for some time.

Admittedly, the 800's performance is limited by the 120-knot regulation, and there are several other airplanes pushing that same number, but the Gobosh 800XP offers the kind of performance you might expect from a fully certified airplane, in addition to the quickest handling in the class---all at a fraction of the certified airplane cost.