What is the altitude you reached with this autotow...

Is there a parachute on the end of the line to slow it down after release, or do you just let it fall onto the runway? How fast is the car going?

@AntaresFilm

4 жыл бұрын

When we tested Autotowing for the Antares 18T, we used a parachute that used to serve as a brake chute extractor for the MIG 21. With the chute in place, we hade the problem of the chute opening whenever the car stopped accelerating during gear changes. With the Antares 23T testing, there was no parachute installed. This meant that the rope would fall a bit faster, but it removed the problem of premature chute deployment. Seeing that the installation we used had no way of pulling in the tow rope as it fell, there was no great advantage to a parachute. Also; with a parachute installed, any crosswind would make the tow rope drift further to the side of the runway. With regards to car speed: The car speed is adjusted over the course of the tow so that the glider flies at optimal IAS the whole time. The speed of the car will thus very much depend on the wind conditions at altitude. While the driver must force him(or her)self to accelerate briskly, the speeds involved are rather unspectacular.

Ich erinnere mich an PKW - schleppversuche mit einer "Fregatte " und Ka6. Ging, aber für ne Platzrunde hat es nicht gereicht:) Es war in den 60igern. Ha!

Liked the video, the music is horrible (I had to mute it). What type of tow line was used?

@AntaresFilm

7 жыл бұрын

We used a 370 m long dyneema line. My apliogies for the music, it is hard to find acceptable music with proper licensing (We do not exactly have Hollywood budgets for our films).

Nice video ; with 370 meters of dyneema what is the altitude you reached ? how log is the runway ? thanks !

@AntaresFilm

7 жыл бұрын

We used a 370 m /1214 ft dyneema rope and 2 km / 1.24 miles of runway. With no water, we reached some 300 m / 980 ft altitude in a combination of fast tow (160 kph / 100 mph IAS) and some headwind (20/30 kph / 10-16 kts) At 902 kg / 1988 lbs, we maxed out at 250 m / 820 ft). A hard runway would probably improve these values. Friction on grass is one of the determining factors with regards to runway length vs. altitude. The idea is to get a safe semi-autonumous launch. The testing with the 18T idling during tow showed that cutting the engine mid tow still left the pilot with enough altitude for a shortened circuit and normal landing. We also view it as important to get the self-sustainer (which is not certified for launching) above minimum legal altitude from ground, so that no aviation authority can (rightly) claim that we use a self-sustainer engine for self launching. Applying engine power during the tow mainly led to issues with overrunning the tow rope and similar. It is therefore advisable to have an engine with throttle control (and a starter motor for safe ground starting). We are now in the process of getting our home airfield certified for car-towing, and I believe that being able to flight-test non-self launchers without getting a tow-plane in will be a nice in-house bonus.

@lorss

7 жыл бұрын

Thanks for your answer ; with 160kph you mean car speed or glider speed ? Thanks

@AntaresFilm

7 жыл бұрын

Hi lorss, IAS means Indicated Air Speed, thus the speed seen on the airspeed indicator in the aircraft. The effect of the headwind was thus to "extend" the length of the runway by allowing the car to go slower, and thus tow for a longer period of time before reaching the end of the runway.

@lorss

7 жыл бұрын

Ok , understood . I have no experience in car towing . just to understand better : on winch we keep an average speed IAS of 110 Kph ( on my glider the VNE on winch is 130kph ) . My question is : why do not use a longer cable with pretty the same winch climbing ratio ? Thanks again !

@egidiobabbi9086

7 жыл бұрын

AntaresFilm a

BMW 5 series?

@AntaresFilm

8 жыл бұрын

We used a BMW 530d Touring with 258 hp and 4WD. The main issue is traction on grass when wet.

@unibrein

8 жыл бұрын

+AntaresFilm I saw the 18T film just a minute later after posting my question, was at Reinsdorf during euroglide 2016, very cosy airfield!

Terrible and loud music

@AntaresFilm

3 жыл бұрын

Music taste can be discussed. We would have preferred no music, but the GoPro had a problem with audio recording. If you can find us some good licence free music, then we will consider it next time we are forced to add music. With regard to loudness, you should be able to adjust this on your device. If it is a PC running Windows, then look for the little loudspeaker icon, bottom right.

@nash0427

3 жыл бұрын

@@AntaresFilm what I intend saying is that the sound should ideally be of the glider, the wind, etc as if the viewer is with you on the flight. This could be superimposed with extremely light backgroud music, bach, vivaldi, Beethoven etc.... on the other hand I've got a pertinent question, whats the smallest airstrip needed for a safe autonomous takeoff with water (max auw), whats the ground roll for electric autonomous take off on grass?