Hacker News new | ask | show | jobs
by sandworm101 1847 days ago
There are a few inconsistencies that lead me to not believe the numbers.

>>It was last seen climbing through 14,000’ and into the undercast, where it disappeared.

>>Department's helicopter was unable to observe the drone when looking through night vision goggles.

If this was heading up to 14k while being chased by helicopters, it wasn't a battery-powered quad. A medium sized drone would have to be powered by IC to perform like that. If it was IC, or even high-powered batteries, it would have been hot enough to look like a flare under night vision goggles.

Or, it didn't go to 14k. It sounds to me like the chase helo lost sight of it and assumed that was because it hit the clouds. The light was dim and the drone had a single flashing light. It is very difficult to judge distance to a single light in twilight. The helicopter could easily have misjudged the distance/altitude. I think the helicopter lost sight because the drone turned off the flashing light. Or maybe the drone lost power and fell. Either way, the chasing helicopter thought it had hit the cloud layer when it fact the drone might have been much lower.

And 14k is 4k above where the police helicopter would have stopped climbing. Aircraft heading above 10k are going to want pressurization and/or oxygen masks. A cop helicopter won't go that high willingly.

>>the fact that it outran two law enforcement helicopters is also concerning

That doesn't mean much. Law enforcement helicopters are nothing special. A fast car or motorcycle can outrun a helicopter in a strait line. And cop helicopters aren't meant to enforce air rules. Every Cessna-172 can outrun a police helicopter. Heck, at night a Cesna-152 could probably evade them, especially if the helos are trying to obey the rules for flying near airports.

Lastly, given the collision risk involved in "chasing" anything in the air, I'm surprised these helicopters were even allowed to give chase. If I were ATC and saw a cop helicopter chasing another smaller helicopter/drone over a populated area I would do my best to stop this before both crashed into a school.

3 comments

It's in the article:

> A source with direct knowledge of the incident's details told The War Zone they believed the drone was highly unlikely to be battery-powered based on the altitude, distance, and speed at which it flew.

Or the reported speeds/altitudes are simply incorrect and rather than a low-IR stealth superweapon this was a smaller battery-powered drone at lower altitudes/speeds.
> If it was IC, or even high-powered batteries, it would have been hot enough to look like a flare under night vision goggles.

I think you're thinking of thermals, unless it's on fire or something it's not going to emit the NIR/visible spectrum light that would be picked up by night vision.

The border patrol helo is an Airbus AS350 with cruising speed around 152 mph and do not exceed at 178 mph
120 knots is normal cruise, 140 knots is fast cruise but that's at sea level. This drops off by 3 knots per 1,000' of density altitude. Airfield elevation at Tuscon is ~2400' and it was 58⁰F at 10 p.m. on Feb 9. Which puts density altitude at ground level around 2900', so the cruise speed drops around 9 knots, to 111 kias and 131 kias.

I agree this UAS would need to be IC-powered due to the range and altitude the UAS supposedly reached, but I don't think the speed was as fast as many folks have been thinking.