Introduction
Account for every flight test including and before W24 where we have clear logs for every flight test.
How often did we crash?
What are the most common causes?
We need to be learning from crashes so this document will hopefully tell us what we should focus on.
Every time someone asks me what these stats are I always do my best to guess, but I want a solid answer.
This analysis will need to be redone in the future as we do more flight tests!
Breakdown
Did Not Crash
Crashed
control system failure
loose motor mount
mechancial failure
Did Not Crash
Unknown
Did Not Crash
Did Not Crash
Did Not Crash
Crashed
Crashed Phoenix Nov 13, 2022 - Phoenix RCA electronic failure, unknown cause, my guess:
transient on bus from ESC regen => HS FET damage, stuck on => melt PDB IC and downstream load (minipix).
Crash Judie Nov 13, 2022 - JUDIE RCA pilot error in controller configuration
Crashed
Phoenix crash → Weather and controller setup
Did not crash
Dec 13, 2022 - Battery Incident RCA
not a flight test
Crashed
poor soldering on ESC (confirmed)
Crashed
mechanical failure (motor mount snapped, possible cause is use of heat gun)
Feb 18/19, 2023 Recording Landing Pad For Training
Did Not Crash
February 19, 2023 Frosted Flakes Validation
Crashed
lots of damage here
poor airframe control authority mechanically
battery voltage sag ← going to call this a secondary cause, we were already crashing before this occurred?
Mar 04, 2023 RFD Range testing and ZP Testing
Crashed
crashed houston
pilot error
Mar 11, 2023 Cornflakes Validation
Did Not Crash
Did Not Crash
https://uwarg-docs.atlassian.net/wiki/spaces/FT/pages/2207383694/Apr+02+2023+Flight+Test+WRESTRC
Did Not Crash
Crashed
prop destroyed
highly likely to be poor solderring 2023-04-09 - RCA for Signal Integrity
April 22-23 Ground Test Sequence
Unknown
Did Not Crash
https://uwarg-docs.atlassian.net/wiki/spaces/FT/pages/2231500801/May+05+-+Practice+Flight
Unknown
May 6th, 2023, Icarus as a Quad
Unknown
Unknown
May 31, 2023 Houston Flight Test
Did Not Crash
Did Not Crash
Did Not Crash
July 9 - Vanny for CV Auto Landings
Did Not Crash
Unknown
Did Not Crash
Did Not Crash
Did Not Crash
Poor tune caused concern.
Landing gear stuck in mud after landing and attempt to take off again
Caused prop damage (maybe motor damage)
Did Not Crash
Did Not Crash
location questionable
Did Not Crash
questionable landing
Unknown
Houston controller config was poor
we didnt crash pegasus but connector concern
Did Not Crash?
Did Not Crash
Did Not Crash
killed some hardware on the ground
Did Not Crash
2023-10-14: Pegasus Hover, ZP3.5 M1, & Pilot Trainning
Failure
Motor Order in software for pegasus
Tubie due to airframe structure
Unknown
Did Not Crash
Did Not Crash
2023-09-30 Pathing Script Flight Test
Did Not Crash
Did Not Crash
good control
poor video
Did Not Crash
Crashed
Pilot error in landing
broken landing gear
2024-03-16 Pegasus VTX + Houston Auto Flight Test
Did Not Crash
2024-03-10 NO-GO Pegasus VTX Flight Test
Cancelled
2024-02-10 Pegasus + Houston Flight Test
Crashed
Weather caused tipping on landings
2024-02-03 Pegasus Efficiency Flight Test
Did Not Crash
2024-01-27 Pegasus + Houston Flight Test
Did Not Crash
battery failsafe saved us from crashing on an over discharge
2024-01-20 Pegasus 4v6 battery Flight Test
Did Not Crash
risk of no loss of comms failsafe
Conclusions
Causes of every crash (including duplicates):
Weather caused tipping on landings (environmental )
Misjudged landing (controls pilot)
Motor Order (controls software)
Wingspare mechanical integrity (mechanical)
Aircraft stuck in mud (environmental)
Signal wire soldering (electrical)
Accidental disarm (controls pilot)
Mechanical Control Authority (mechanical)
Motor Mount Broke (mechanical)
Signal wire soldering (electrical)
Weather caused lack of control (environmental)
Controller configuration (controls software)
Electronic component failure (electrical)
Loose Motor Mount (mechanical)
Categorizing Even More (removing duplicates):
Environmental (3)
Controls (4)
Mechanical (4)
Electrical (3)
Total (14)
Fairly even split here I guess lol
We should be careful about a few cognitive biases when reviewing this data
sampling bias
we don’t have a lot of data here.
differences in airframe have a large impact on likely failure modes.
survivorship bias
Just because something doesn’t appear in the list doesn't mean it’s not a concern.
In my opinion we’ve had so many close calls because of motor order and poor soldering concerns, however, these are underrepresented in the failure modes observed