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Oct 18, 2019, 04:55 AM
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I was not sure if I could do half speed FPV approach. So that I could approach the runway from the side at half speed. - I tested it. Speed was max 47 km/h, well below stall speed. Altitude max 17 m and vario min -1 m/s. Flight was very easy. Much easier than helicopter simulator. Airplane style HH gyros kept aircraft very steady and aerodynamics fine tuned it. I also rised thruster slowly up at end. It landed automaticly. Touchdown might look some wild, because camera is so low near groud, but its pretty much soft and neat. Half speed flight is real fun and I could do it more. Altough I am not sure how much ampere I used. Maybe below 100A. I didn't get that telemetry information.

Groud effect is bad for my link connections...

MrJan´s F-35B FPV half speed test (0 min 32 sec)

Thrusters position (see picture below):
Last edited by MrJan; Oct 18, 2019 at 06:47 AM.
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Oct 18, 2019, 09:13 AM
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By the way this is not expensive hobby. I think I can do it well under $1000/year. The motors of this plane cost some but rest of components i recycled from my older aircarfts. Foam and fibers are cheap. I only maintain one airplane at a time (and one seaplane in summer place).

But this aircraft is some complicated and difficult to maintain. Every component must work properly and together or its gone. And I have quite many different parts there. Itīs full off everything. - And then I did pilot error, last week.
Last edited by MrJan; Oct 23, 2019 at 03:55 AM.
Oct 19, 2019, 02:29 AM
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I have now tested all the different flight modes, two different ways, FPV and LOS. Horizontal flight, half speed flight and vertical landing. And I have done both transitions from short take off to horizontal flight and from horizontal to slow speed and then vertical. (Vertical landing need some more practising).

I have not used more than 1800 mAh at once. Often much less. It is less than half the battery capacity. And at this point I donīt know how much more I can do. If battery voltage collaps, it is kind of disaster. I'm not sure if I want to study how batteries behave exactly. It has lot of work to do.
Last edited by MrJan; Oct 19, 2019 at 03:07 AM.
Oct 19, 2019, 03:59 AM
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What I would need is stress test for main batteries. Then upper limit for continious ampere use. And alarm limit for used mAh.

For example. I make limit for throttle use so it can not exceed 120 A. Then I do stress test for every battery with that 120 A continious use. And mark useful mAh to them. And at end I must adjust alarm for those mAh before flight.
Last edited by MrJan; Oct 20, 2019 at 01:05 AM.
Oct 24, 2019, 02:56 AM
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And here is FPV flight with all flight modes and transitions. It is 1000 mAh flight and max 120 A current. Max horizontal speed 90 km/h. Short landing speed 30 km/h. On video you can hear telemetry information (you might need earphones) and other information in text format.

MrJan´s F-35B STOVL EDF FPV (1 min 17 sec)

Below flight modes:
Last edited by MrJan; Oct 24, 2019 at 04:39 PM.
Nov 10, 2019, 09:09 AM
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I have made some new flight tests. It looks like that basic horizontal flight "cost" about 60 A, half speed (thrusters 45 deg.) 120 A and vertical takeoff or hover cost about 160 A.

On the video there is 1200 mAh flight with vertical takeoff and hover landing. It is 500 m flight, max 15 m altitude, max 160 A, vario min - 1,9 m/s, speed max 48 km/h. - I still have difficulties FPV fly helicopter. It feels like an airplane, slow flyer, but it's not.

MrJan´s F-35B STOVL EDF vertical takeoff and landing test (1 min 16 sec)
Last edited by MrJan; Nov 11, 2019 at 11:50 AM.
Nov 15, 2019, 09:07 AM
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This project proceed step by step. This time I tested complete FPV VTOL flight. I did both 90 degrees transitions, vertical takeoff and landing. It was about mile round, this time clockwise . The steering feel was good all the time and all speeds. Before approaching I made a steep turn at half speed middle of transition. Pretty cool. (It was not planned. It was more like navigation error). This time I did it right, full throttle just in case. Last time it was stall… On the video can also see how long it takes to slow down at cruising speed.

  • max speed 90 km/h
  • max altitude 33 m
  • min vario -2,8 m/s
  • min voltage 3,2 V/cell
  • max current 163 A
  • capacity 1700 mAh

MrJan´s F-35B EDF complete VTOL flight (1 min 38 sec)
Last edited by MrJan; Nov 16, 2019 at 03:54 AM.
Nov 15, 2019, 09:19 AM
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Last edited by MrJan; Nov 15, 2019 at 10:26 AM.
Nov 16, 2019, 06:41 PM
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Ran D. St. Clair's Avatar
Nov 17, 2019, 07:52 AM
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This is some funny. I don't know what I am doing. I accelerate and slow down the aircraft few meters above runway. I need hundreds of meters long area for that due to the weight of this aircraft and high cruising speed. Basicly I do exactly same as conventional jets when they takeoff from runway or land, but I do it few meters higher. - Well, I should be happy I don't need landing gears.
Nov 17, 2019, 11:59 AM
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If you think you have enough thrust you should be able to "flare" aggressively, essentially stalling the wing and using it as an airbrake. A bit hard to do in FPV, because then you lose all ground references
Nov 17, 2019, 02:38 PM
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It is high alpha position. My FPV camera pointing some down so I can do it - in theory. Have to try it with a simulator.
Nov 17, 2019, 03:01 PM
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I didn't know they do also Rolling Vertical Landing.

The first Shipborne Rolling Vertical Landing (SRVL) (3 min 19 sec)
Nov 20, 2019, 02:47 AM
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This is also intresting. Notice how the computer calculates the glide slope (touchdown point).

GS=5 deg
AOA=10 deg
Approch speed = 150 km/h (scale 50 km/h)
Final speed = 60 km/h (scale 20 km/h)

F-35B SRVL Warton Shipborne Rolling Vertical Landing Sim (1 min 34 sec)
Last edited by MrJan; Nov 20, 2019 at 10:16 AM.
Nov 24, 2019, 01:18 PM
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This is difficult. On the video there is my FPV rolling vertical landing. Basically I must do it manually because I donīt have accelerometers or auto level. And my pitch gyro control is not good enough under 20 km/h speed (or the use of throttle).. But if there is good will, you can find glide slope in the video (blue).

MrJan's F-35B STOVL Rolling Vertical Landing (0 min 54 sec)
Last edited by MrJan; Nov 24, 2019 at 01:29 PM.

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