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Crash analysis

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Hi folks!
New Typhoon H guy here.

I was hoping someone could analyze my somewhat of a crash. After my CCC mission, I switched to RTH, and everything was going as normal. However, when it landed (on flat pavement), the motors would not shut off as usual. After a few seconds, the H started pitching and then tilted forward into the pavement, scraping the front props and ending on its back. Luckily, no damage as far as I can tell. This thing is less than a week old and I am really having a blast with it, but now I am kinda nervous as to why this happened. Here is the link to look at the telemetry. Any help would be appreciated!

Telemetry_00045.csv

Thanks!

Ed
 
Hi folks!
New Typhoon H guy here.

I was hoping someone could analyze my somewhat of a crash. After my CCC mission, I switched to RTH, and everything was going as normal. However, when it landed (on flat pavement), the motors would not shut off as usual. After a few seconds, the H started pitching and then tilted forward into the pavement, scraping the front props and ending on its back. Luckily, no damage as far as I can tell. This thing is less than a week old and I am really having a blast with it, but now I am kinda nervous as to why this happened. Here is the link to look at the telemetry. Any help would be appreciated!
Telemetry_00045.csv
Thanks!Ed
I can see where you switched from CCC to RTH and also when it landed and then tipped, but I see no cause for this in the telemetry. Did you hold the kill button in to try to kill the motors after it touched down? Have you done RTH landings previously in this location? Did you touch the sticks at all after it landed?
 
It's really a good idea to stay on the sticks for landings. Holding the throttle stick down and disarming the motors would have prevented this. We don't know what your right hand was doing during this process.
 
Thanks for the replies. No, I did not hold the kill button down nor did I do anything with my left hand. It never did that before and I was used to it landing and shutting down the motors on its own. I will make sure to hold the throttle stick down and disarming the motors manually from now on. My right hand was controlling the pitch and roll as it was coming down, but once it was properly positioned for landing, I did not move the right stick any more.
 
Hi folks!
New Typhoon H guy here.

I was hoping someone could analyze my somewhat of a crash. After my CCC mission, I switched to RTH, and everything was going as normal. However, when it landed (on flat pavement), the motors would not shut off as usual. After a few seconds, the H started pitching and then tilted forward into the pavement, scraping the front props and ending on its back. Luckily, no damage as far as I can tell. This thing is less than a week old and I am really having a blast with it, but now I am kinda nervous as to why this happened. Here is the link to look at the telemetry. Any help would be appreciated!

Telemetry_00045.csv

Thanks!

Ed
Hi, to avoid crazy landings I always hand catch it and kill the motors in the air. Works great for me and is safe.
 
Remember to wait for the engines to rev down, it has happened to me twice in the first weeks of flying the H. Now I know to land it, hold the throttle stick down once it is on the ground and wait for the motors to drop the revs (sound changes significantly) and that is when I press and hold the red start / stop button. Works for me.
I often hand catch it too, takes a bit of practice and works very well, just be careful with the sticks...
 
Remember to wait for the engines to rev down, it has happened to me twice in the first weeks of flying the H. Now I know to land it, hold the throttle stick down once it is on the ground and wait for the motors to drop the revs (sound changes significantly) and that is when I press and hold the red start / stop button. Works for me.
I often hand catch it too, takes a bit of practice and works very well, just be careful with the sticks...
I don't touch the sticks at all. I just "place" the H flying a bit above and away from my head Then grab the landinggear leg - then kill the motors with the red button. Works!
 
Thanks for the replies. No, I did not hold the kill button down nor did I do anything with my left hand. It never did that before and I was used to it landing and shutting down the motors on its own. I will make sure to hold the throttle stick down and disarming the motors manually from now on. My right hand was controlling the pitch and roll as it was coming down, but once it was properly positioned for landing, I did not move the right stick any more.

I had the same yesterday. Manual landing, touched down, throttled back and pressed the kill switch, but the Typhoon pitched foward slightly, which I corrected, it then rolled gently backwards ending up balancing on the skids and rear motors. No damage to the props as the surface was a thick ground sheet and motors were throttled back. The only explanation I can put this down to is the surface was slightly uneven, so on landing the Typhoon tilted forwards slighlty, there was a wind of 10mph which might have disturbed it too, the Typhoon self corrected, I had given an backwards input too, which combined initiated a backwards tilt, but by the time it had pitched backwards there wasn't enough lift to correct so when I tried to catch the backwards movement it had shut down.

Just a combination of small factors occuring at one time.
 
I had the same yesterday. Manual landing, touched down, throttled back and pressed the kill switch, but the Typhoon pitched foward slightly, which I corrected, it then rolled gently backwards ending up balancing on the skids and rear motors. No damage to the props as the surface was a thick ground sheet and motors were throttled back. The only explanation I can put this down to is the surface was slightly uneven, so on landing the Typhoon tilted forwards slighlty, there was a wind of 10mph which might have disturbed it too, the Typhoon self corrected, I had given an backwards input too, which combined initiated a backwards tilt, but by the time it had pitched backwards there wasn't enough lift to correct so when I tried to catch the backwards movement it had shut down.
Just a combination of small factors occuring at one time.
Many people have found when landing of uneven ground or in wind it is easy to tip the H over. One method that has worked well is to hover a few inches above the ground and hold the kill switch in. The H drops nicely into place and you never get a broken prop.
 
Something that may be helpful for landing. If you always take off and land with the front of the H facing into the wind you'll be dealing with a simple control correction factor. Worst case is you land with the H leaning into the wind a little bit. If it rocks back you only need to input a little forward stick to correct. If it rocks forward you only need to input a little aft stick to correct. If landing the H with the nose facing some other direction that into the wind you can end up dealing with relatively complex control corrections that combing forward and aft with pitch in either direction.

Remember that a landing is not complete until the props have stopped turning. Until that moment we need to be cognizant of what the H is doing and respond with control inputs accordingly. "Fly" the aircraft until the motors have fully stopped. If using RTH/auto land, the automated control process is pretty much over once the skids hit the ground. The H really doesn't know when it is on the ground. The program did what is was supposed to do in getting it home and on the ground. If the motors cut, great, but don't depend on that to happen, especially if wind conditions are causing the H to to be unstable with the skids on the ground. In full scale a landing is not complete until the aircraft is parked and tied down. A great many landing incidents have occurred simply because the pilot stopped flying the airplane before the airplane had stopped "flying". We read about a large number of drone landing incidents that occurred for the same reason.
 
After my CCC mission, I switched to RTH, and everything was going as normal. However, when it landed (on flat pavement), the motors would not shut off as usual.

I understand you have been doing this with success. Don't do it any more.:eek:
In RTH, when it gets above or close to you, switch to Angle Mode and land it yourself.:)
 
Many people have found when landing of uneven ground or in wind it is easy to tip the H over. One method that has worked well is to hover a few inches above the ground and hold the kill switch in. The H drops nicely into place and you never get a broken prop.

Thanks Steve, we live and learn.
 
Skeets, to reiterate standard landing procedure, when the TH touches the ground, hold the throttle fully down until the motors come to idle. Make no other control inputs after it touches the ground. Be careful not to move the throttle/yaw stick to either side, just straight down. Then, while holding the throttle down, press and hold the red kill button until the motors stop. This may take a few seconds. Of course, try to choose a fairly level landing spot.
Other procedures, such as hand catching or skipping the throttle-down step can be added to your skill set in the future, understanding that the risk of problems is higher.
 
Skeets, to reiterate standard landing procedure, when the TH touches the ground, hold the throttle fully down until the motors come to idle. Make no other control inputs after it touches the ground. Be careful not to move the throttle/yaw stick to either side, just straight down. Then, while holding the throttle down, press and hold the red kill button until the motors stop. This may take a few seconds. Of course, try to choose a fairly level landing spot.

Yes. I have been using this procedure since. This incident happened in flat and level blacktop and have used the manual landing procedure (on flat and level blacktop) without incident. HOWEVER, I was testing out the Wizard just now and was landing by putting it into Home then switching it to angle mode when it was about 10 feet off the ground and manually taking it down the rest of the way when it HAPPENED AGAIN! I was holding the throttle down (down button) when it touched down and it just started rocking back and forth and tipped over on its back blades, breaking one of the blades. I think I am just going to have to practice hand catching!
 
Yes. I have been using this procedure since. This incident happened in flat and level blacktop and have used the manual landing procedure (on flat and level blacktop) without incident. HOWEVER, I was testing out the Wizard just now and was landing by putting it into Home then switching it to angle mode when it was about 10 feet off the ground and manually taking it down the rest of the way when it HAPPENED AGAIN! I was holding the throttle down (down button) when it touched down and it just started rocking back and forth and tipped over on its back blades, breaking one of the blades. I think I am just going to have to practice hand catching!
That's fine, but you really need to find out what's going on with the unstable landings. Any chance the accelerometer calibration needs redoing?
 
That's fine, but you really need to find out what's going on with the unstable landings. Any chance the accelerometer calibration needs redoing?

I could do that again, but I have already done all three calibrations several times.
 
I could do that again, but I have already done all three calibrations several times.
Maybe time to consider the conditions surrounding the calibrations you've done. Accelerometers on a dead level surface? Just a thought. Just a stab in the dark.
 
Just for confirmation about your startup routine:
Always set the H on a level surface to launch away from all buildings, underground piping, concrete pavement or underground electrical wires.
Once you press the power button don't move the H until it is fully booted. Once it's booted, let it sit a few minutes with the motors off.
If there is no wind take it up 10-15', let it hover and do a slow 360 degree yaw. It should turn in place with little or no drift. If it drifts over a couple of feet there is a problem with the accelerometers or the calibration.
When descending to land if you see any instability when it's a few feet above the ground, take it back up again and retry the landing. If it continues to do the same thing, try landing 40 or 50' away from that spot.
 
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Just for confirmation about your startup routine:
Always set the H on a level surface to launch away from all buildings, underground piping, concrete pavement or underground electrical wires.
Once you press the power button don't move the H until it is fully booted. Once it's booted, let it sit a few minutes with the motors off.
If there is no wind take it up 10-15', let it hover and do a slow 360 degree yaw. It should turn in place with little or no drift. If it drifts over a couple of feet there is a problem with the accelerometers or the calibration.
When descending to land if you see any instability when it's a few feet above the ground, take it back up again and retry the landing. If it continues to do the same thing, try landing 40 or 50' away from that spot.
Thanks, but this is exactly what I have been doing for over 15 years. (except for avoiding concrete pavement....I did not know this may be an issue...I do usually take off on blacktop.) I have always been extra careful about my startup routine...almost to a fault. There is absolutely nothing I did, or didnt do that would have caused this to happen. My routine is 1) carry craft to a flat, level and hard spot. 2) Turn on radio and wait until it completely boots up. 3) Turn on aircraft and wait until it completely boots up. 4) wait until everything is done calibrating, beeping, and locking on. 4) Take off into a hover about 10 feet or so up. 5) Move sticks all around to make sure everything reacts properly with little to know drift 6) Take off. If I do anything different, or if the aircraft behaves, or sounds unusual in any way, I will turn everything off and start again.
I tried hand catching last night, and although I was a little apprehensive at first, it was actually easier than I expected. I plan to do that from now on.
 
Thanks, but this is exactly what I have been doing for over 15 years. (except for avoiding concrete pavement....I did not know this may be an issue...I do usually take off on blacktop.)
Please be assured I was not being critical. You are obviously an experienced pilot. I'm simply trying to eliminate possibilities. Concrete generally has steel reinforcing which can play havoc with the compass. I've seen that occur when a pilot used asphalt to launch but it was next to a concrete curb. Of all the possible difficulties in flying, landing always seems to be the most difficult. Each pilot seems to find a method that suits them. Many have discovered that moving the left stick fully down is difficult without also pushing it a little left or right. Hope you find a method that works for you.
 

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