“NOUT” dedicated towplane.
An ambitious and realistic project for gliding!
This study is born from the observation of these three points:
- A brief history of French tow planes
- Park Aging current tow planes (CDN = Rallye, DR400, …) in a difficult economic climate is a heavy burden for gliding clubs. The technical and economic inadequacy of these aircrafts are the genesis of a gliding problem.
- Emergence microlight tow planes ULM in response to this problem:
The microlight world seizes this niche by offering low consumption planes, but not appropriate to this mission, bringing no additional performance (including takeoff), causing an unprecedented regulatory singularity (Microlight towing certificated gliders) and causing a decline in terms of security (no aircraft certification).
Whatever the solution used (Certified CDN modified aircraft, CNRA or CNSK dedicated aircraft, modified microlight aircrafts) we can notice that the propeller disks are too small which indicates a loss of efficiency resulting in poor power output and therefore a vertical speed almost identical to all current technical proposals.
Given this situation, it is now emergency that gliding world define itself the tow plane he really need and produce a tool only for the purpose of towing in the current economic situation.
But what are these needs: ?
- Be climb efficient (much more than what exists today), and not just the regulatory need.
- Be sober
- Consume a cheaper fuel than the current 100LL
- Be inexpensive to buy (eg Kit building within the clubs)
- Be simple
- Be silent
- Be strong
- Be repaired in situ with conventional knowledge in aircraft maintenance
- Be a two seat to form tow pilots
- Provide visibility to the ground and in flight
- Be handy the ground and in flight.
- In three words Ideal tow plane must be available , strong and profitable .A judicious choice of parameters airframe and power plant must be done to bring the performance largely above to current existing tow planes. Its operating point must be the highest possible rise (Vertical speed) to the towing speed ( 120 km / h +/- 10 km / h).
The body structure must be Classic (wood, fabric and steel tubes) to reduce manufacturing costs and because much of the work maintenance can be undertaken by volunteers in gliding clubs . The activity then becomes popular with social involvement of glider pilots in the creation and consideration of their equipment. The project then there is the profitability with a reduced cost but also a short towing cycle times associated with low cheaper fuel.” Nout ” fulfills all these conditions taking into account the requirements that only glider pilots know about.
The project “ Nout ”
- Resumes design from the base (energy of flight) in order to identify the parameters maximizing the climb at 120km / h.
- Includes all the constraints inherent in the practice of gliding.
“ Nout ” is therefore the first aircraft designed specifically for the mission of Towing gliders. Its design is based on the knowledge developed until 40’s (apogee of propeller aircrafts).
The chosen engine is LF39 by D-motor , its choice is motivated by:
- Its power (130 hp @ 3300 rpm max / min) ~ 120 hp continuous
- The simplicity
- Liquid cooling
- The number of cylinders (less acyclism a 4-cylinder)
- Its specific power (~ 85 kg equipped to 130 hp)
- The ability to consume MOGAS
Planetary gearbox is added to it to make possible the installation of the propeller necessarily large to be truly adapted to its towing mission.
“ Nout ” is above all a plane for Aerial Work designed by glider pilots for glider pilots to respond mainly to the Towing Mission of gliders modern and ancient
- flight envelope close to the glider (modern and old)
- Climb speed multiplied by 2 (6.7 m/s for a single-seat glider, 4.8 m/s for a two-seat glider)
- vastly superior performance to take off
- Classic Structure strong , feasible and repairable in gliding clubs
- Economics ( Automotive Gasoline or 100LL) 21 l / h
- Silent against residents
Designed specifically for the gliding clubs needs:
- Start from a blank sheet, sized by gliding pilot, “Nout” is an economic and efficient tow plane responding to the unique mission of towing gliders.
- The choice of a wooden + steel structure and fabric kit technologically simple and robust, is a major advantage for clubs, both for purchase and for maintenance.
- The liquid cooling maintains a guarantee of the engine operating temperature in all phases of flight (up, down, wait)
- The flight envelope, close to the glider makes “Nout” perfectly suited for towing modern gliders (Vt ~ 130 km / h) and old (Vt ~ 100 km / h) without tainting the climb performance.
- As a whole, “Nout” is capable of climb speed that is other than twice what can a MS893E for only half of its power.
- The high diameter propeller of “Nout” not only confers notable performances but silence expected by residents of aerodromes.
- Consuming motor gasoline, Kit proposed and built by volunteers in clubs, this plane can only be the vector of a popular revival of Gliding.