Letter From Geoff Steele

Pilots lying on their belly

"Hi Koen: I edited two books for David Myhra on the Hortens' developments.  One of the books contained extensive interviews with people who built, and flew the various aircraft.

In answer to your questions, here's my recollection of the text material:

Was it easy to get in and out?

Yes....dorsal hatch over the pilot's back could be released in flight and just 'blow away' from the plane, allowing quick egress in emergencies.  The seat belt holding the pilot to the seat also was a quick release; one could then invert the aircraft (at altitude), or just go into a gentle climb and push yourself away from the airframe prior to stall.
Was it hard to adjust to this kind of seating?Each aircraft had a short 'range' of the seat structure that would accommodate pilots of different heights.  Seat pitch was mostly 'fixed' re: angles at waist and knees, etc. to ensure best comfort and blood circulation.  Seat configurations and pod lengths had to be modified and made longer for taller pilots.  This also affected center-of-gravity and placement of counterweights to ensure the C/G remained in proper location.

Was it comfortable?

Most all pilots reported the prone seating position to be VERY comfortable.  Rudi Opitz flew the sailplanes both in Germany during the 1930s, and he also competed in a U.S. National soaring contest here, using a Horten IV (1952, I believe).  He flew for hours at a time on all contest days and I don't recall his reporting fatigue; he just got lost in the vast expanses of the countryside a couple of times and had to land out, losing points.  Otherwise, he might have won the Nationals that year; he was third, I believe.

Did you expect to get tired neck after a long time? (This one really puzzles me. Hang glider pilots don't have this problem, I was told.)

The Hortens were equipped with padded chin rests that took the strain off the neck....like putting your head into a pillow when sleeping on your stomach.  The head and chin also were slightly lower than the upper torso, which made the head/chin position quite 'natural' and comfortable...  This resulted from much experimentation by Reimar on best ergonomic pilot positions for long endurance flight.  I can't speak to hang glider pilots' experience.  Al Bowers could best comment on that; he's experienced.

What is the difference between both head positions?

Basically the difference between lying down in a padded, reasonably form-fitting couch, with your knees in padded cups and your calves at about a 30-degree angle up behind you....with your toes dropped into stirrups on the rudder pedals to help hold them in place while flying.  All of the seat (couch) was aluminum contour, with good, comfortable padding material that 'breathes' to allow airflow to the body.  The chin is positioned in the chin rest (mentioned above) to mitigate stress and strain needed to 'hold' the chin in a raised position while lying down (which over time would become VERY uncomfortable and stressful on neck muscles).  In a 'normal' upright pilot position, the head is held in position by neck and upper torso muscles.  The body's designed for this, so stress isn't normally an issue.

How was the steering bar? Felt good in hand? To close to body? Was it weird to have your elbows pointing outwards?

Can't comment on this, other than to say that Rudi Opitz seemed to really enjoy flying the IV; he said it was restful.  Of course he was an "innovative" pilot, ready and willing to try anything.  He was the Messerschmitt company test pilot on the Me-163, so that was pretty innovative, too.  I suspect compared to the drama of flying a chemical 'bomb', tailless wooden fighter plane with no landing gear (only a skid) at 500+ miles per hour, flying the restful Horten IV probably was a pleasure, no matter what slight discomfort there might have been in doing so, comparatively. You could probably build yourself a little 'working model' of the cockpit of the IV and experience these things for yourself.  We're all intrigued by the same questions.  When I was on an inventory research discovery session at the National Air & Space Museum with a small team from the Vintage Sailplane Association here, back in the 1970s, we found (crated) the center section of the Horten VI, with the wings (also crated) closeby.  I could have shinnied into the crate and lay down on the couch to get the feel of the cockpit and controls, but was prevented from doing so by the curator accompanying us (and the bird droppings covering the crate boards and the plane, as well as the delicate 'aged' nature of the airframe and fabric).  I'm 5-feet 8 inches in height (about 'normal' I guess, compared with standard German pilots' heights in the 1930s).  Rudi Opitz and I were about the same height, and he flew the VI once or twice, as I recall.  The control bar was fairly close to the chest, from my observation.  So also the flap and spoiler handles.  But nothing was "weird" except the instruments were on a panel imbedded in the wing root on the port side, had faces in 'reverse', and were read via a small mirror in front of the pilot's eyes.  Very creative method of putting them where they had 'room' and out of the pilot's forward vision -- so critical on a landing approach.

Hope this is helpful to you... Best regards,Geoff SteeleHuntersville, NCUSA"