FlightLog Archive

Flying the Stemme S10-VT - Oct 2002

As we approach the Christmas season, I've often had dreams of a fantasy sailplane gift, and a Stemme S10 seems to be one of the ultimate fantasy machines, combining the best of soaring and powered flight. I've seen a Stemme in the Arlington pattern, but hadn't yet made contact with the owner. I was searching on the SSA website, and found that Sky Sailing, at Warner Springs airport, NE of San Diego, had a leased-back Stemme S10-VT available for rent! I was headed to San Diego for business in October, and arranged to see how this fantasy airplane really flew. Although the weather on October 26th was cool and mostly cloudy, it still looked flyable, although not exactly soarable when I drove through the mountain pass into Warner Springs airport.

The first few things that I noticed about the Stemme were the dual main landing gear, allowing normal taxiing, plus the long wingspan of 23 meters/75.5 feet, giving a max glide ratio of 50:1. Garret Willat, from Sky Sailing, mentioned that there have been a number of recent ADs for the Stemme series, especially due to concerns over the engine compartment. However, when things are working, the airplane is a great touring and soaring vehicle. The cockpit is quite impressive, with decent head and shoulder room for a side-by-side two-seater.

After a walk around and cockpit pre-flight, we warmed up the engine a few minutes on the ground, and then had a short launch. The S10-VT has a Rotax 914FS1 engine, generating 115 hp, giving us with a good climb rate right after takeoff. The stick feel and maneuverability were better than I expected, so we used it to peel right into some thermaling hawks just after takeoff, and climbed quickly under power to the southwest into a hole in the overcast.

We shut down the engine and retracted the propeller into the nose at around 5000' (2000' AGL) in some good lift, and began climbing in a combination of rotor and wave in a clear area between cloud streets to the SW.

The Stemme was stable but decently responsive in turns. As expected, I needed a good dose of rudder at the start of steep turns to compensate for adverse yaw. Flap use took a bit of getting used to, but later became part of the normal reaction to speed-to-fly changes as we moved from areas of sink to lift. Although the day initially looked to have no soaring potential, the bits of wave-like lift and the Stemme performance allowed me to climb to 8600' along the edge of rising clouds. Visibility was excellent, and the view down those long wings to the vertical winglets about 37 feet away was impressive. I could definitely get used to this!

As in most areas of good wave lift, you often have to penetrate some strong areas of sink en route or on return. Today was no different, and as we headed back to Warner Springs, I got a bit low in strong sink on the return, and we began scratching at about 1500' AGL. It was nice to have that engine as a backup, but I really wanted to make it back in pure sailplane mode if we could. We scratched out a few hundred more feet to allow a smooth 50:1 glide back to the pattern. Approaching the Sky Sailing pattern, the Stemme was easily configured with gear down and landing flaps, allowing for a very comfortable 62 knot approach. The spoilers provided precise control and allowed me to make a decent 2-point landing on my first try, engine stowed. I only used the engine for about 15 minutes, including the ground warmup time, during the 1.4 hour flight. Very neat sailplane! If you can afford the reported high level of maintenance, the Stemme is definitely a well performing bird with tremendous possibilities for touring and cross-country, without being tied to a towplane or land out and retrieval concerns.

Now if anyone is thinking of chipping in for a Christmas present...!