The Look That Kills
Fri 1 Sep 2006This afternoon’s Ping contained an article with the headline RAAF gets ‘look and shoot’ tech. Australia’s F/A-18 Hornets are being equipped with new high-tech targeting systems.
Boeing’s Joint Helmet-Mounted Cueing Systems (JHMCS) technology …
allows pilots to pick a target just by looking at it.
By aiming a crosshair, projected on the helmet visor, over the desired target and pressing a button, pilots can quickly and easily aim weapons and their radar.
JHMCS technology also displays aircraft altitude, airspeed, gravitational pull, angle of attack and tactical information on the visor …
This is new, is it?
I distinctly remember being told about a very similar technology in 1973! It was being tested by a group of US pilots in helicopter gunships in Vietnam.
Now, I was in an infantry unit at the time and my information is admittedly second-hand, but my RAAF mate who had served in Vietnam would have known what he was talking about. And I certainly had my interest in technology way back then. When I asked searching questions about the system, I could tell he wasn’t making it up. I’m sure it was before 1974 because that was when I transferred to an armoured unit.
The 70’s System
The 70’s system wasn’t quite as sophisticated as today’s. There was no heads-up display and no crosshair projected on the visor; The crosshair was scratched-in permanently over one eye. There was a gyroscope in the back of the helmet. This was simply wired in through A to D converters to a micro-processor. This controlled the motors which drove the machine-gun turret mounted underneath the helicopter. The turret was constantly pointed in the direction of whatever the pilot was looking at.
These were the days before stealth was necessary, so the radar was constantly on and ranging. If the pilot saw something he didn’t like, he could engage it immediately.
The system was nick-named The Look that Kills.
Recording a Target
The micro-processor also had a memory so, instead of engaging straight away, the pilot could just record the target, loop around and then engage it from a better angle. This was particularly useful when patroling along a river or road and the pilot caught only a glimpse of the target off to the side.
Once the pilot had recorded a target, the turret no longer tracked the pilot’s helmet. It locked on to the target, awaiting the engage signal.
Software Bugs
The major problem with the system, as reported by the pilots, occurred during these “loop-around and engage from a different angle” scenarios. The helicopter would pop-up over a ridge a few kilometres from the target, the ranging system would detect direct line-of-sight to the target and the machine guns would start automatically. At least that’s how it was supposed to happen.
Sometimes, after only a couple of rounds had been fired, the radar would signal “out of range” and the weapons would shut down. Apparently there’s nothing worse than flying towards a now-alerted enemy at top speed, but with an inoperative weapons system. You’ve just got to keep going and fly right over the top of them because to peel off to one side would just present a larger target to the bad guys.
I can just imagine the assembly-language programmer responsible for the piece of code which engaged the weapons before checking the range: I knew that should have been a JNE instead of a JEQ.
I’m pretty sure it would have been assembly-language. I don’t think there were FORTRAN compilers for micro-processors in those days. And I don’t think the DoD mandated the use of ADA until about a decade later.
September 3rd, 2006 at 15:42
I can’t imagine trying to write a system that complex in assembly language, though I suppose it was done all the time. The mind boggles…