Hi NW1,
Back with you,
Our (probably my) depth of knowledge on Concorde’s operational performance is not as high as I would like. I’ve never heard anyone mention the “operational band between 450-600”, although, as we transfer you to Shannon by 8 degrees west it isn’t of much practical significance to us, but still nice to know.
I’m not surprised that Concorde is unaware of some of the problems, as there has always been a “parting of the waves” scenario, particularly during the acceleration period, that rightly should be transparent to the flight crew.
The problem of going out against the inbound flow was always the weakest part of my post. I just threw it in for completeness, and I was happy to concede that one to Ock1f.
Regarding inbound descent. If its too busy for individual co-ordination between the Strumble sector and the Brecon sector, (that’s the one you hit inbound after Exmor), they agree FL310 15 miles before Numpo for all TMA inbounds, with the equivalent for you being FL310 15 before Exmor, would that be much of a penalty for you? How about FL290 once in awhile?
In respect of the descent problems as you approach Malby. There are a number of East and West-bound routes that Concorde converges towards. This converging scenario doesn’t easily lend itself to our usual method of operation.
As I’m sure you are aware, Latcc is very big on parallel headings. If your pointing north-east towards Malby and there is Westbound traffic radar vectored on the north side of G1, at various levels, we only clear you to safe levels on top of that traffic until you too, can be placed on a radar heading on the south side of G1, unless we are certain there is no risk.
We are not allowed to clear you down through traffic on the understanding that we will remember to turn you when you hit the southern boundary of the airway. It’s been tried, but it’s a ****** when you lose the frequency!
As you approach the southern boundary of G1 you start to integrate with the TMA inbound flow and until the corner is turned, it can require tedious (for both of us) step-down descents on top of descending traffic.
If we asked for a 320kt descent speed, would you need some warning and an earlier descent point? How much earlier say than from FL370 unspeeded? If left up at FL370 unspeeded, then given 320kts when say passing through FL280, is that going to mess up your descent profile and cause problems with your FL140 40 from OCK?
Looking at the outbound picture, the perceived wisdom at Latcc is that radar headings whilst accelerating to supersonic speeds were not an option, due to sonic boom considerations. If necessary would five or ten degrees left away from Eire, crossing the boundary with Shannon about 10-15 miles south of the normal Lesu exit point (used to be 51N 08W) be acceptable?
I assume delaying acceleration even by 20 or 30 miles is out of the question except in dire straits, is that right?
I would hopefully not need to use the above alternatives on a regular basis, but just to know what or what is not available in my armoury of tools if necessary, would be extremely useful.
The point I made about the ground speed, which we will have displayed when we go to Swanwick, isn’t really answered by asking you for a “snapshot” speed as you accelerate. If you can imagine 2 jets equidistant from a conflict point at around the same speed, you can tell just by looking at the radar that it’s going to be a problem. Even if one of them is going twice as fast, it’s still possible to “eyeball” it, as the faster one will need to be around twice the distance from the conflict point for it to start becoming a problem. But if an aircraft, say Concorde! is initially around the same ground speed as the possible conflict, then a short while later is 1.2 times its ground speed, then 1.5, 1.7, etc, my initial assessment of “no problem”, can start to become “well, maybe a ten degree turn” or “better go for twenty, maybe twenty five”, “and how about some descent just to be on the safe side”. Very often because of the uncertainty and a natural inclination for caution, the traffic misses you by many miles laterally or thousands of feet below vertically. Once we get the ground-speed readout, our (my) conflict prediction skills should improve.
Just out of curiosity, is an initial cleared level after acceleration commences of say FL390, whilst we ensure that traffic in the way is vectored clear, but always planning on continuous climb, an acceptable procedure?
How does it work for you at the other end (JFK)? I thought New York liked to get traffic down early, do you have special routes in/out or just the normal STARS/SIDS?
It goes without saying that none of the above will of any interest to the Latcc (and other) Ace Controllers, who will by now be deriving huge amusement from the old boys embarrassing disclosures.
Keep in touch
Overload