I suppose this is on topic as (an inconsequential) simultaneous VHF transmission took place.
Graybeard.
The Contran shown in post 1465 was conceived by an airline Capt. in the US, in response to the KLM/PanAM collision on Tenerife in 1977.
Interesting post Graybeard, and almost
totally wrong. Contran was indeed conceived following the Tenerife disaster - but not by your US airline captain. That would be a Mr Rutty, in my personal experience a
little man – in my opinion of course.
He patented the device.
He didn’t – Contran Patents were all in my name. What he
did Patent was a system
so simplified that it was, for all practical purposes, useless. And he had the gall to use, as part of his US Patent Application, a letter of mine to Flight International describing Contran.
…. a device which needs be only some simple added circuitry in a VHF Comm, not a separate LRU, Line Replaceable Unit.
Therein lies the difference. Rutty was a DC-10 captain, I fixed avionics. Following me? Take a look at the US Patent Office records and see the not so subtle differences.
Even VHF Comm designers could see the drawbacks to the idea. … pilots would soon get in the habit of keying the mic before the present transmission is finished, in order to be next to talk. As soon as two or more do that at the same time, the system is fragged.
Wrong! Again, ……… see the not so subtle differences. (do you really think that an RTCA, FAA TSO’d and UK CAA Approved piece of kit would allow that?)
There may have been other factors that doomed it, such as NIH, Not Invented Here.
Two things mainly. Rutty’s unworkable lash up, and his constant pounding on US doors (including his Senator’s) left the whole anti-blocking programme with a credibility problem. Secondly, the
abysmal support of the Contran licensed manufacturer caused even those who’d fitted the system to lose interest. Apart from Airbus that is, which couldn’t see a problem so
refused to action formal requests from airlines to provision passenger aircraft – but equipped their own Beluga transports. Aircraft wings from UK being more valuable than pax.
To get back to your ‘the system is fragged’. Boeing carried out their own human factors lab tests and, as a result, offered the kit as a customer option. Proof? See below. Maybe it’s time to resurrect it.
