YouTube user and drone pilot Denis Koryakin ("Денис Корякин") recently published a video showing a small drone's trip to an altitude of around 33,000ft. Operating a drone at that altitude would be against regulations in many places, not to mention risky to commercial aircraft.
That said, this particular ascent appears to have taken place in a remote region of Russia near the Siberian city of Strejevo, and there don't seem to be any altitude restrictions on small drone flights in Russia, so he didn't technically break any laws.
According to Koryakin's video description, this "drone experiment" intended to get the drone to an altitude of 10 kilometers, which is just under 33,000ft and about the cruising altitude of passenger jets. The on-screen display shows the drone's speed hitting 13 meters per second at one point, and Koryakin explained that temps went down to -50°C (-58°F) when the drone reached an altitude of around 8,000 meters (~26,000ft).
The video translation reads (H/T DPReview user ShaiKhulud):
March 9, 2018. Experiments with drone are still in progress. Goals for this flight are: reach a height of 10km and return to the launch site without accidents.
By popular demands, by my own desire and with a help of my friends we've added an air temperature gauge.
Because of the thermometer inertia, temperature is displayed with a slight delay.
The outside ground level temperature was around -10 C.
Max temperature during flight was around -50 C at 8000 m. altitude.
DVR footage and HD footage is slightly out of sync (by a few seconds) because of the frame skipping.
In the video description, Koryakin also lists the parts used to construct and control the drone, all of them readily accessible to anyone who wants to replicate it. Components include Cobra brushless motors, Gemfan carbon nylon propellers, and Sony li-ion batteries. The drone weighed around 1kg / 2. 3lbs.
Disclaimer: Always check applicable local laws before trying something that might be dangerous or potentially illegal. DPReview does not condone or encourage illegal activity.
. dpreview.com2018-3-24 20:51