"Laser based speed sensors are in R&D phase, Airbus have done trials. Cost is an issue, so defense applications are likely to be first customers."
I was measuring the velocity of red blood cells in the skin with a laser doppler flowmeter 30 years ago, so it is hardly a new technology.
'Scuse me for buttin' in…
[The laser has to face "forwards", but high powered modern solid-state lasers are cheap as chips now. You could probably buy a dozen for the price of an electrically heated pitot-tube]