Radio Frequencies V Channel Numbers

[Cat O' Nine Tails]

Question.


Given the choice of using current methods of frequency change E.G Call london on 132.475 or the option to use Call london on Channel 148, which would you prefer?

I personally would prefer the fewer digits associated with channel numbers. The pilots that I have posed this question to, all seem to prefer the ease of less digits. Any one have any good reason why not? or serious objections?

[TheOddOne]

I do hear 'three two decimal four seven' from time to time. Personally I think that missing out the initial 'one' (and of course we droppped the last 'five' years ago) is the way forward. It's completely unambiguous. The initial 'one' is totally redundant.

Of course, if we were to go to 'channel' we would presumably need four digits rather than three, which with the addition of the word 'channel' might make it more long-winded than present. And of course, all the radios in the world would need their dials changing. I couldn't possibly remember that 'three four decimal four seven' was 'channel one three seven eight'!

The key here is unambiguity. By using the 'decimal' we know we're talking about a frequency, nothing else. Likewise, if we say 'feet' we know we're talking about a vertical measurement, not a horizontal one. When reporting DME, we say 'five point two', not 'five decimal two'

Interesting point, though.

BTW, how long is VHF voice comm going to last? For large public transport a/c ops it will almost certainly be replaced by an automated datalink system in the next few years, whether it's 'son of ACARS' or another system - we'll see. That'll further marginalise the GA types who won't/can't participate (I can't see how it can work for single crew ops, for instance).

For large transport types, I can see that soon the uplink of ATC instruction will input directly into the a/c systems, leaving the crew mostly in a monitoring function and steering the aircraft on the ground.

Cheers,
TheOddOne

[HEATHROW DIRECTOR]

How would the pilot interpret the frequency change if it was expressed as a channel number? If new radio gear had to be fitted which shows channel numbers the cost would be frightful. The alternative would be that he had to look it up on a table to determine the frequency then input it in frequency format to the radio. Where's the benefit?

I have used channel numbers to great effect in the past, but they were employed by base aircraft with radios which only had half a dozen channels on the selector. When they left base area frequencies had to be given in standard format for them to use other equipment.