Uploaded January 2021 | Updated September 2026, 2 weeks ago
#FPV #sub250 #interview
Patreon: patreon.com/michaelrollins
Instagram: instagram.com/themichaelrollinsshow (@themichaelrollinsshow)
* UPDATE from Ben Goddard (edited for clarity) *
I don't *think* it was covered as I'm not fully through this yet, but their rational for .55lbs is more fully explained in the paper linked below on page 11 (and DJI's rebuttal linked below as well).
Highlights include that they're planning for a drone to be dropped from *500ft* onto someone - for a 250g quad, that means 57mph by their calculations, which assume you're flying in a VACUUM. The 80 Joules of energy associated with this impact is something they indicate (with references) to have a 30% chance of lethality if it it were to impact someone's head. Given these assumptions, the weight limit doesn't seem arbitrary and almost generous, I'd say. But you could certainly argue with their assumptions.
For example: their drop calculations concluding that a .55lb quad generates 80 Joules of energy was estimated assuming a vacuum - which DJI points out that if you just included a drag coefficient the weight to generate 80 J from 500ft would be ~450g. Also after we've gotten a few more hours under our belt collectively it would seem to indicate their calculations are a bit conservative when the estimate 1 ground fatality per 20,000,000 flight hours - which we seem to have exceeded many times over. But when your chances are 1/20,000,000 - you can really roll the dice a lot before you "win."
We also seem to be creating amazing stuff with these limitations. I have to say, getting smacked with a 450g quad dropped from 500ft or traveling at an equivalent velocity sounds devastating though....
faa.gov/regulations_policies/rulemaking/committees/documents/media/uasrtfarc-102015.pdf?fbclid=IwAR0HQDhlgJ1pNBhff0v3J6v7T80V5qwZYlB9w3yWfR8oR8j-VUuv9MfH4l4
DJI's rebuttal to 250g being arbitrarily low: dropbox.com/s/t8o4zaojpmwg3qs/Defining%20a%20Lowest-Risk%20UAS%20Category.pdf?dl=0&fbclid=IwAR3osu3Pi16ageuFMGXEEfpeC6rsTDHvpEfXP8ysApOn2PfX7MMKL-V6T3c
* End Quote *
With the delivery of the FAA Remote ID rule the foreseeable future of FPV has been defined, but the writing has been on the wall for a while now. While we all hope that some way will be made available for us to continue flying the ways that we have grown to love, it’s always wise to be prepared.
A few folks have started pushing innovation into the sub-250g space. Tommy Tibajia (Ummagawd) and Bob Roogi (KababFPV) are two of the folks with the most coherent ideas on how to get HD footage in something resembling modern FPV flight with a sub-250g package.
The truly intriguing thing is that Tommy and Bob are approaching it from the exact opposite ends. Tommy wants to get to 249.9g and still have a 5” quad, while Bob has started as small and light as he can and is working up. The results of both of their efforts are truly fascinating.
You can find Tommy here:
youtube.com/c/ummagawdFPV
ummagawd.com
You can find Bob here:
youtube.com/channel/UC4yjtLpqFmlVncUFExoVjiQ
fpvcycle.com
Extra information from the episode:
Bob’s Tiny Drone: youtu.be/T6OBImq09dE
RDQ Fighting the FAA: racedayquads.com/pages/faa-legal-battle-to-save-fpv
Unsolvable Math Problem: snopes.com/fact-check/the-unsolvable-math-problem
FAA sub-250g Part 107 Rule is unconfirmed
#FPV #sub250 #interview
Patreon: patreon.com/michaelrollins
Instagram: instagram.com/themichaelrollinsshow (@themichaelrollinsshow)
* UPDATE from Ben Goddard (edited for clarity) *
I don't *think* it was covered as I'm not fully through this yet, but their rational for .55lbs is more fully explained in the paper linked below on page 11 (and DJI's rebuttal linked below as well).
Highlights include that they're planning for a drone to be dropped from *500ft* onto someone - for a 250g quad, that means 57mph by their calculations, which assume you're flying in a VACUUM. The 80 Joules of energy associated with this impact is something they indicate (with references) to have a 30% chance of lethality if it it were to impact someone's head. Given these assumptions, the weight limit doesn't seem arbitrary and almost generous, I'd say. But you could certainly argue with their assumptions.
For example: their drop calculations concluding that a .55lb quad generates 80 Joules of energy was estimated assuming a vacuum - which DJI points out that if you just included a drag coefficient the weight to generate 80 J from 500ft would be ~450g. Also after we've gotten a few more hours under our belt collectively it would seem to indicate their calculations are a bit conservative when the estimate 1 ground fatality per 20,000,000 flight hours - which we seem to have exceeded many times over. But when your chances are 1/20,000,000 - you can really roll the dice a lot before you "win."
We also seem to be creating amazing stuff with these limitations. I have to say, getting smacked with a 450g quad dropped from 500ft or traveling at an equivalent velocity sounds devastating though....
faa.gov/regulations_policies/rulemaking/committees/documents/media/uasrtfarc-102015.pdf?fbclid=IwAR0HQDhlgJ1pNBhff0v3J6v7T80V5qwZYlB9w3yWfR8oR8j-VUuv9MfH4l4
DJI's rebuttal to 250g being arbitrarily low: dropbox.com/s/t8o4zaojpmwg3qs/Defining%20a%20Lowest-Risk%20UAS%20Category.pdf?dl=0&fbclid=IwAR3osu3Pi16ageuFMGXEEfpeC6rsTDHvpEfXP8ysApOn2PfX7MMKL-V6T3c
* End Quote *
With the delivery of the FAA Remote ID rule the foreseeable future of FPV has been defined, but the writing has been on the wall for a while now. While we all hope that some way will be made available for us to continue flying the ways that we have grown to love, it’s always wise to be prepared.
A few folks have started pushing innovation into the sub-250g space. Tommy Tibajia (Ummagawd) and Bob Roogi (KababFPV) are two of the folks with the most coherent ideas on how to get HD footage in something resembling modern FPV flight with a sub-250g package.
The truly intriguing thing is that Tommy and Bob are approaching it from the exact opposite ends. Tommy wants to get to 249.9g and still have a 5” quad, while Bob has started as small and light as he can and is working up. The results of both of their efforts are truly fascinating.
You can find Tommy here:
youtube.com/c/ummagawdFPV
ummagawd.com
You can find Bob here:
youtube.com/channel/UC4yjtLpqFmlVncUFExoVjiQ
fpvcycle.com
Extra information from the episode:
Bob’s Tiny Drone: youtu.be/T6OBImq09dE
RDQ Fighting the FAA: racedayquads.com/pages/faa-legal-battle-to-save-fpv
Unsolvable Math Problem: snopes.com/fact-check/the-unsolvable-math-problem
FAA sub-250g Part 107 Rule is unconfirmed
