Lange has a beautiful new purpose-built factory on the Zweibruecken airfield. The molds shown here hold the wings for serial #25. Serial #17 will be delivered to a customer this week.
Click on the images for full-size pictures !
Antares Trial Flight
Zweibruecken, Germany
4-September-2005
(edited 31-March-2007)
The Antares 20E motor-glider project was started to create a pilot-friendly, electric-powered, top-performance 18m/20m glider. I've been interested in this project since I saw the flying test-bed (based on the DG-800) at the Aero 2001 show at Friedrichshafen, and then the prototype Antares 20E at Aero 2003. The concept was born out of frustrations with the trade-offs inherent in gas-powered motor-gliders. Can electric drive prove practical, as well as providing the efficiency and reliability we expect from electric motors ?
On one of my regular business trips to London, I hopped Rynair down to Frankfurt, picked up a rental car, and drove down to visit the Lange factory at Zweibruecken, Germany. Ola Thorsen, an engineer at Lange, kindly agreed to meet me on a Sunday and brief me, and weather permitting I can go for a spin... So, how does the Antares stack up ?
Lange has a beautiful new
purpose-built factory on the Zweibruecken airfield.
The molds shown here hold the wings for serial #25.
Serial #17 will be delivered to a customer this week.
Click on the images for full-size pictures !
The safety briefing is detailed and lengthy, covering the numerous systems, safety features, and emergency procedures of the Antares. While actual operation of the machine is blissfully simple, as with all motor-gliders one must be very aware of system operation in case of malfunction. For Antares one must correctly and safely manage the available power in the batteries rather than fuel.
While the Antares is simple to operate, there are myriad systems to make it so. Battery cooling during high discharge, battery discharge rates, motor heating, battery cell voltage leveling by automatic discharge, battery heating to nominal operating temperature during flight... All these things one must understand, though ordinarily no action is required.
Want to fly in very cold weather but avoid discharging the batteries with the self-heaters ? Can be done, but understand the limits on available power and/or restart the heating system well in advance of using the prop. And so forth. The dedicated computer screen gives you detailed information about battery voltage, estimated available power, temperatures, etc. Ola's careful safety briefing covers theory of operation, displays, warnings (presented visually and via voice), emergency procedures, and walks through the entire manual (unfortunately only in German at this time, so I was not able to study prior to my visit).
Standard operating procedures are really very, very simple. The emergency procedures are not too bad, and many failure modes are carefully non-threatening. Sink rate with the motor out and windmilling is only around 250 fpm, with no major pitch-up or other handling excitement. Learn when to operate the emergency shutdown (fire only), emergency wheel extension, power cycle, what if the control computer fails, etc.
A gust of wind blows through the office signalling the thermals are starting to kick off... after 3 hours of study, time to get going !
The wings are very heavy, being filled with batteries and the battery systems. The glider comes with an excellent self-assembly dolly to avoid lifting the wings, and it was easy to hoist the wingtip out of the trailer and into the dolly. Ola quickly maneuvered the wing around and inserted it, repeated with the second wing, and used an assembly tool to easily draw the wings together and line up the holes.
Ola uses the well-engineered wing dolly to easily insert the
wing and ease it into position. The two wing-pin system
and rigging tool make it very easy to insert the wings,
get them perfectly aligned, and insert the pins.
No "opposite wing pops out" hassles.
One person assembly is really no problem; this is faster
to rig than any of my current toys.
Everything hooks up automatically except for the large
battery connectors in the wing-roots (shown here).
Here we're assembling serial #4 for me to take for a spin.
The cockpit is big and comfy, even for my 6 ft 1.5 inches. Nice adjustable seat-back and rudders provide comfy seating for people of greatly different sizes and proportions. After the detailed briefing, everything seems already familiar. No idea how to operate the alien (not an ILEC SN10) flight computer though !
All controls fall readily to hand. Really nice layout !
Ola gives me the cockpit briefing.
Push the big stick forward and the houses get bigger.
Stepping through the automated checklist requires a translator for now !
It's amazingly painless and quiet to get underway. Turn the key on, push the throttle forward, and in 10 seconds the engine extends and engages and we're taxiing comfortably ! No fuss trying to start the engine ! Nothing else to do ! In the Antares even the pitot-static switching and microphone switching to the headset mic are automatic. A big improvement !
Nice positive rudder steering for taxi. Its easy to taxi even with no extra space on the taxiway. No tendency to go up on the nose !
It's wide ! Wheels at wingtips with 10 meters on each side
require careful taxiing on the 10.2-meter wide asphalt.
Here I've got the main gear right on the edge of the pavement.
Note the air vent in the bottom of the wing for battery cooling,
which will close automatically later.
Easy to line up on the centerline for pause prior take-off.
As advised, for my first take-off I accelerate gently. Stick full back as usual with full aileron to pick the wing up. The wing-tip comes up quickly and easily off the runway. No flap changes required; take-off and best climb are achieved with the +2/L flap position; no need to start with negative flaps and cycle positive.
Raise the tail at about 65kmh. Some bobble as the tail comes up, looks a bit discombobulated and disorderly. Accelerate a bit more and lift off at around 95km/hr, but perhaps I let it lift off a bit early as its unsteady. Ola kindly attributes this later to a bit of turbulence at this point on the runway.
Acceleration and take-off.
Climb to 100 meters (safe turn-around altitude), flip the switch on the panel to retract the gear, and throttle back to 100 amps for better efficiency. Seems to impair the climb quite a bit so I increased power to 110 (at around 275 volts, its a lot of power). Climb is extremely positive at the 51 knot blue-line. The IGC file shows something like 12 seconds to gently accelerate to lift-off, then 2.9 minutes to 1900 feet, for an average of 650 fpm climb (mostly at less than max power). This used about 1/4 battery capacity (which had been topped off to 100% during my briefing).
The noise level during climb is very low, though one uses the provided light-duty headset to be sure of hearing any audio warnings. Big improvement from "use a proper headset when running the engine or you will damage your hearing".
About 700 meters with some wisps in front of me over the town of Zweibruecken ought to be adequate !
To shutdown, just pull the handle back. It's recommended to confirm in a mirror that the automated system properly moves the prop vertical prior starting retraction (it does, totally painless). In it goes ! Around 15 seconds to clean gliding configuration, with the motion of a single handle. No cool-down time or other duties in the cockpit.
In short, easy, painless, and without the gratuitous excitement delivered by some other machines !
It's a glider !
The Antares handles easily. Its easy to maintain proper speed during climb, only mild trim changes during shutdown and retract. The first weak thermal is easily managed, though I struggled a bit trying to properly trim the glider. In normal maneuvering the controls are light and harmonized. Maximum turn reversal at thermalling speed runs out of rudder and shows high rudder force at the extreme deflection. (Lange: Nobody noticed before but the rudder cables in serial #4 were slightly mis-adjusted, we'll fix it.) Anyway, very easy to climb out.
There's a customer glider ready for delivery later in the week. It is clearly in need of further factory testing ! As duty demands, Ola will join me in around 15 minutes.
Putze around for a bit and get used to the glider, then wander back to the airfield to watch Ola's launch from above. He lifts off without any perceptible bobble raising the tail, so its obviously possible to do this smoothly with a bit of practice.
While its quite hazy, to our surprise and delight it turns out to be a decent soaring day. Can't just hang about Zweibruecken ! We start North-East and quickly find its possible to run-and-bump with no need to circle. Moderately fast run across a big forest to the town of Landau, near Mannheim in the Rhine river valley.
Dave over Landau.
Stop to tank up in a nice strong thermal then North along the edge of the high country, and West around the big Ramstein US airbase control area. Further North-West around the Baumholder restricted area, West to the Luxembourg border, then South-East along the French border, across the Moselle river, and head back home, taking care to detour a bit North of course to stay out of the Saarbrucken airspace. Flying in Germany is kinda like flying through a maze with the airspace restrictions, which makes me appreciate all the more our remaining freedoms in USA.
I'm flying with a moving map that shows airspace boundaries, a computer
I can't figure out (no final glide and German only), and a paper map.
Ola may need to do further work to the panel he's flying (above)
prior delivering the plane to its new owner !
Both planes were equipped with FLARM though mine was inoperative.
On the final leg towards home it gets fairly weak. The Antares is quite nice in the soft thermals (though I'm still fighting a bit with the trim). Maybe I'll just fly local for a bit longer in the gentle evening thermals... Sudden immense panic as I realize I'd meant to leave for my return trip already ! I'll never hear the end of it if I miss my return trip to London !
Ola got some very nice air-to-air shots.
Here you can see us circling together over the Moselle river,
Dave with a huge grin,
in the haze somewhere near Ramstein,
and a shot showing some typical German scenery.
Radio the tower, gear down, and dash back to Zweibruecken. As advertised, its totally gentle in the pattern, land on the spot, and pull off at the intended taxiway. Oops, its the wrong taxiway. No problem to instantly raise the motor (10 seconds from clean to under power) and fast-taxi to the correct runway exit. The German lady's voice warns me I'm using the motor with the spoilers unlocked, but this seems prudent for a downhill taxiway and the wheelbrake at the end of the spoiler travel ! At least I think that was what she was complaining about. English will be available Real Soon Now. Easy taxi back to the Lange factory, shortly joined by Ola.
Happy return ! What a beautiful day !
Ola couldn't help himself but run the motor and snap a few shots
above the clouds before landing (after all, its important to properly test this
glider prior customer delivery).
Sure was hazy !
I helped Ola a bit putting the plane away, but had too little time to hang out and ask a million questions. Rush off to return to London, only to find I really did allow excess time back to Frankfurt-Hahn and my flight is delayed by an hour ! Just made the last train from Stansted back into London. Time to spare, go by air... Regret that I didn't have a bit more time to check out how it behaves with the prop windmilling and so forth, but given what I hear from friends of mine who've flown Antares (and tried this) I'm confident its very benign.
The Antares is magnificent. Handling is extraordinary with roll faster than some 15-meter ships. My intro flight lasted 4:21 for 270km distance by OLC score, but actually more by our circuitous route. The propulsion system is powerful, quiet, and simple to operate. And the glider is easy to assemble and manage on the ground.
OK, I'm hooked. The more I thought about flying this machine, the more I had to have one. And, owning any motorglider requires good service and support. One thing led to another, and I became the North American agent for Lange Flugzeugbau. We took three experienced motorglider mechanics over to Zweibruecken for factory training in November 2006 (including Rex Mayes from the West coast).
My Antares 20E arrived just in time to display at the 2007 SSA convention in Memphis. I leant my glider to Roger Buchanan to fly in the Seniors, and had my first couple of flights in it at Seminole Gliderport - absolutely fantastic. One other Antares 20E just arrived in USA and will be licensed shortly, Roger's will arrive in the next few weeks, and others will be arriving throughout 2007.
Hope you enjoy this and please email
with questions or comments,
Best Regards, Dave "YO"
Dave.Nadler@nadler.com
Lange Flugzeugbau - Antares web site
Map view of Dave's trial flight
IGC file of Dave's trial flight
Soaring magazine advertisement
Roger Buchanan's article on the Antares 20E, SSA's Soaring magazine, June 2004.
USA Sailplane Racing Association
Dave's 2005 Blog from Uvalde USA 15-meter Nationals
Dave's 2004 Blog from Uvalde USA 18-meter Nationals
