Vojec
Member
Recently I had a serious accident, crash with my heavy X8 multi. So I ask all of you to help me solve this riddle, what, why, how it went wrong ...
I'll try to describe the whole situation step by step. Before I start here was my current setup .
X8 -frame
WKM with GPSV1 and IMU V1 - firmware 5.16
DJI IOSD
4S 17400mAh
Motors MT2814 - 11 710kv
Tiger ESC 30A
Graupner 12x6 props
Receiver Frsky TFR4 - with Futaba TX T8FG Super
immersion 5.8Ghz 600MW
Opale Parachute
Total weight = 7.7kg
For two years I did not upgrade, replace anything just frame. 4 months ago I moved the whole existing setup from the flat octo 8 to coaxial x8. In those 4 months I have tested and flown at least 30 times without any problems in all modes: Manual, Atti, GPS. For safety reasons I ordered and mounted on frame rescue system - Parachute Opale. Check COG multicopterja and tested the whole rescue system and it works well.
That day I went on hill (attach image bellow) recorded landscape over the fog. On the hill I prepare and start to fly like every other days. I replaced the 3 batteries. I flew between 300 - 500m away. I flew exclusively in Atti mode. When I put the last reloud of batteries, check the GPS Tracker also and fly in a straight line with a constant speed of 5 - 6m/s. At a distance of 532m or near 2min of flight, I suddenly lost all signals: Futaba 2.4Ghz, 5.8Ghz FPV Video Camera And GH2 camera, 2.4Ghz Quanum telemetry. I looked into both monitors FPV and Rec one, both show just snow. Quanum telemetry shows: no signal.
It lasted 2-3 seconds. X8 is already roll over and started to fall. For a moment (3 sec) I get all the signals back and immediately added elevation. X8 began to stop falling down (upside-down position). Adrenaline flown through my body like a drug, time has stopped - seconds seemed like minutes. I raised both hands up in order to get the best signal. On both monitors and telemetry Quanumu I got the video image and telemerty info back. This moment lasted for 1-3 seconds and then I lost again. I immediately activated Rescue System - Paracshute on Futaba switch, then with both stick indicate for shutting down the motors and watch how the x8 disappeared in the fog. I was thinking only one thing: whether the parachute opened??? I sent an SMS to GPS tracker for crash coordinates. There was no SMS reply.
To make a long story short; X8 I found with the help of Quanuma telemetry - follow signal to appear. When I checked the whole heli, I saw that the servo did not activate the parachutes- start position.
On the other hand, I was lucky that 8kg falling bomb from the sky (200m above) did not kill someone. Flying over uninhabited region.
Facts:
- On the hill were placed satellite dishes and were oriented in all directions.
- I flew in Atti mode: no effect on GPS
- No wind
- I was flying above the fog, humidity was not included
- with that electronic I was flew over 1KM on sea and wast landscape with no problem.
That day I called the Kopterworx who told me what could went wrong. Yet I will not reveal their clues, because I would like to hear from you other possible clues, observation, of what cause a sudden drop and crash.
Here you have raw video (I needed 2 days I got a clip) and the overall situation of Flight (Google Earth).
View attachment 15366
Any hint are welcome.
Thank you all guys.
I'll try to describe the whole situation step by step. Before I start here was my current setup .
X8 -frame
WKM with GPSV1 and IMU V1 - firmware 5.16
DJI IOSD
4S 17400mAh
Motors MT2814 - 11 710kv
Tiger ESC 30A
Graupner 12x6 props
Receiver Frsky TFR4 - with Futaba TX T8FG Super
immersion 5.8Ghz 600MW
Opale Parachute
Total weight = 7.7kg
For two years I did not upgrade, replace anything just frame. 4 months ago I moved the whole existing setup from the flat octo 8 to coaxial x8. In those 4 months I have tested and flown at least 30 times without any problems in all modes: Manual, Atti, GPS. For safety reasons I ordered and mounted on frame rescue system - Parachute Opale. Check COG multicopterja and tested the whole rescue system and it works well.
That day I went on hill (attach image bellow) recorded landscape over the fog. On the hill I prepare and start to fly like every other days. I replaced the 3 batteries. I flew between 300 - 500m away. I flew exclusively in Atti mode. When I put the last reloud of batteries, check the GPS Tracker also and fly in a straight line with a constant speed of 5 - 6m/s. At a distance of 532m or near 2min of flight, I suddenly lost all signals: Futaba 2.4Ghz, 5.8Ghz FPV Video Camera And GH2 camera, 2.4Ghz Quanum telemetry. I looked into both monitors FPV and Rec one, both show just snow. Quanum telemetry shows: no signal.
It lasted 2-3 seconds. X8 is already roll over and started to fall. For a moment (3 sec) I get all the signals back and immediately added elevation. X8 began to stop falling down (upside-down position). Adrenaline flown through my body like a drug, time has stopped - seconds seemed like minutes. I raised both hands up in order to get the best signal. On both monitors and telemetry Quanumu I got the video image and telemerty info back. This moment lasted for 1-3 seconds and then I lost again. I immediately activated Rescue System - Paracshute on Futaba switch, then with both stick indicate for shutting down the motors and watch how the x8 disappeared in the fog. I was thinking only one thing: whether the parachute opened??? I sent an SMS to GPS tracker for crash coordinates. There was no SMS reply.
To make a long story short; X8 I found with the help of Quanuma telemetry - follow signal to appear. When I checked the whole heli, I saw that the servo did not activate the parachutes- start position.
On the other hand, I was lucky that 8kg falling bomb from the sky (200m above) did not kill someone. Flying over uninhabited region.
Facts:
- On the hill were placed satellite dishes and were oriented in all directions.
- I flew in Atti mode: no effect on GPS
- No wind
- I was flying above the fog, humidity was not included
- with that electronic I was flew over 1KM on sea and wast landscape with no problem.
That day I called the Kopterworx who told me what could went wrong. Yet I will not reveal their clues, because I would like to hear from you other possible clues, observation, of what cause a sudden drop and crash.
Here you have raw video (I needed 2 days I got a clip) and the overall situation of Flight (Google Earth).
View attachment 15366
Any hint are welcome.
Thank you all guys.
Attachments
Last edited by a moderator:
My only other guess is that aliens were using the aerials on the hill to relay a message home and swamped all the frequencies you were using 
