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@bUpdate Update the title following the format: Jan 01, 2023 - RCA Name

...

Postmortem owner

Hamza Ali

Airframe

Tube

Related incidents

Apr 09 Flight Test

Incident date

Approx. Damage Costs

$25

Report Date

🔮 Executive summary

During the April 09 flight test, we crashed our Tube aircraft and damaged a LiPo. The LiPo was overheating and we contacted the necessary offices and departments to insure that it was immediately disposed of in a safe and secure manner.

⏱ Incident timeline

Describe (approximate) timelines, cross-correlate with telemetry/video recordings/etc if any.

-30s - Pilot lost orientation of aircraft

+/-0 - Pilot crashed aircraft

+1m - Noticed no puncture in any of the cells, decided to transport back to the bay

+ 2h Got to the bay, noticed battery was slightly warmer than other 3S packs

+ 2h30m - Attempted to communicate with safety office, got deferred to special constable (off hours)

+ 2h40m Special Constable came, investigated the situation

+ 3h Special Constable attempted to contact the safety office, unsuccessful, directed to contact the fire department

+ 3h30m Fire department concluded no risk, and left

+4h Special

...

⏱ Incident timeline

Describe (approximate) timelines, cross-correlate with telemetry/video recordings/etc if any.Constable re-attempts contacting the safety office

+4h30m Safety office / chemical spills people are successfully contacted, they pick up our batteries

⛑ Postmortem report

Instructions

Report

(warning) Leadup

List the sequence of events that led to the incident.

We were unsure of the specific procedure to deal with damaged LiPo batteries and escalated the situation until we got into contact with the departments who were aware of how to deal with the problem.

🙅‍♀️ Fault

Describe what didn't work as expected. If available, include relevant data visualizations.

We had to call the special constable as well as the fire department in order to successfully dispose of the batteries in a safe manner

👁 Detection

Report when the team detected the incident and how they knew it was happening. Describe how the team could've improved time to detection.

  1. Noticed that the battery was deformed after crash.

  2. Noticed that the battery was slightly warmer than expected when inventorying batteries for discharging.

2. We saw that there was a problem when we noticed our LiPo batteries were getting warmer than we expected to as we began discharging our other batteries after the flight test. In doing so, we decided to contact the special constable and solve the immediate solution, get more information in order to develop proper procedures.

🙋‍♂️ Response

Report who responded to the incident and describe what they did at what times. Include any delays or obstacles to responding.

  1. Pilot in Command + Visual Observer visually inspected the battery and observed no punctures or heating.

  2. Team member in charge of discharging batteries decided to escalate the situation.

    1. Team Leads were made aware of the situation.

    2. Team Leads decided to call safety office → timeline as follows.

🙆‍♀️ Recovery

Report how the user impact was mitigated and when the incident was deemed resolved. Describe how the team could've improved time to mitigation.

  • We escalated the issue and got into contact with the special constable, which lead us into contact with people who were not necessary

  • In the future, we should directly get

🔎Five whys root cause identification

Run a 5-whys analysis to understand the true causes of the incident.

  • Non-clarity on battery-disposal techniques.

🗃Related records

Check if any past incidents could've had the same root cause. Note what mitigation was attempted in those incidents and ask why this incident occurred again.

  • past crashed batteries did not heat up after crashing.

🤔 Lessons learned

Describe what you learned, what went well, and how you can improve.

  • Need detailed operating instructions.

  • Concise 911 calls if batteries catch on fire during flightline.

✅ Recommendations for future

Actionable Recommendation

Reasoning

Purchase a dedicated Ammo can for damaged batteries

It is unsafe and creates extra unnecessary risk to mix our good batteries and bad batteries

Keep a bucket of sand to smother future situations

It is one of the only few ways to contain a LiPo fire

Update LiPo operations procedure and Flight test response procedure (add situations on disposal fire, physical damage)

We need to know what to do when an incident like this happens again in the future