Distances on Contact with Heathrow Director
 

On first contact with Heathrow Director (120.40) aircraft are given a distance in miles from the airfield.
I've often wondered if this distance includes the base leg/final approach vectoring which the a/c will have to travel to intercept the ILS or is it a guestimated distance based on current position and traffic levels?

Thanks as ever!!
z...

It is the actual track distance which the controller anticipates that the aircraft will fly until it touches down. This takes account of everything you mentioned,

..... and usually equals your altitude in '000s of ft x 3 ....:D . If it is more than that you are off on the scenic tour of West Berkshire (landing easterlies) or Berkshire then back into Essex (westerly ops)....

..........and if it's less than that, ooops, best push the nose down ;)

...... or dangle the dunlops...:p

<<and usually equals your altitude in '000s of ft x 3 >>


Sorry, Topbunk, I did that precise job for 31 years and that rule of thumb never entered my mind!!

HD

Surely you're havin' a larf --- you must be the exception then;) :p

Edited to say that I feel priviledged to teach an old dog a new trick ....:ok:

Topbunk - No, not at all. The distance to touchdown at Heathrow depends almost entirely on traffic ahead and not necessarily on the altitude of the aircraft. Obviously if someone is way too high then adjustments are made but the pressure to maintain the spacing is such that some a/c have to expedite descent and others might get a few more miles than their range suggests.

The directors know the ranges of those on the ILS and the spacing required (taking into account VORTEX, weather, etc) and simply add the gaps to produce the range from touchdown. Allowance is made in the calculation for the fact that those on the ILS are doing 160, those on base 180 and those downwind 210. With experience it becomes quite easy.

I'm sure that my ex-colleagues will agree...

HD

I was poking fun - it's just that frequently (maybe 90% of the time) the formula I suggest is the response from your ex-colleagues!

Regardless of that, I know that the LHR (and LGW) system of ATC is amongst (if not THE) best around when it comes to calculating EAT's and track miles (but then again you don't often need EAT's elsewhere:* ).

TopBunk, add my 27 years to HD's (hi Bren) 31 and I've never heard of your rule of thumb either. HD's an Old Dog but he invented most of the tricks...

Then it must be the well done tricks of your colleagues on previous sectors and joint effort / experience, that in fact most of the time, it comes very close to TopBunk's equation. :ok:

In a certain UK document I have read (noise, CDA, LP/LD approaches) there was a section regarding use of a software tool to help you calculate the track or perhaps air miles, is such thing being used as well?

FlightDetent... and others. I think there must still be some misunderstanding amongst pilots of how air traffic controllers actually function. Long, long ago I showed round a BA Command Course at Heathrow. During the Q&A sessions at the end one guy asked "where is the computer which tells you what headings to give us". I merely pointed at my head and he was duly amazed. Most of my UK expereince has been in busy LTMA airspace and up until the time I retired there was absolutely no computer assistance available which determined the timing and nature of instructions passed to pilots. There are tools for conflict alert and tools to provide information regarding flight plans to contollers but the actual decisions regarding instructions given to pilots are determined by the controller without any outside prompting (except when they are under training and a training officer maybe nudging them).

ATCOs are fully aware of the alt divided by range rule - they practice it every time they do their emergency training, but the question posed by this thread concerned the Heathrow Final Director. His method is to look at the radar display, count the aeroplanes and apply his skill and experience to determine the ranges from touchdown to be passed to the pilots.

At ALL times the controller decides this in his head - there is no external magic box which does it for him. Twice during my time at Heathrow we trialled computer assisted approach sequencing tools and rejected them either because they were unsafe or because they could not better a properly trained and experienced controller.

of course, descent from min stack is usually issued at 24 miles so any further ranges should always match up with the alt times 3 rule.

FlightDetent

I think you are referring to FAST - Final Approach Spacing Tool.

I don't know if it is working or has been tried, but I doubt it would work any better than the (highly trained) ATCOs eyeball.

HEATHROW DIRECTOR

You'd be amazed at how little some pilots understand about ATC. I have been told that at Heathrow the controllers start at BNN and take one aircraft off each stack going clockwise!?.. I replied that actually it is anti-clockwise.

G W-H

<<I replied that actually it is anti-clockwise.>>

Gawd - you're giving away trade secrets there Giles!!!

Yes, it was FAST fairly recently and CAAS (Computer Assisted Approach Sequencing) about 25 years ago.

FAST-Forget About Safety Tool

Feckin' Awful Sequencing Tool

FAST.....

We trashed that a few years ago... The terminal folks found that they were doing just as good as the machine if not better, and to make the machine to better ( as good as the controller ) it was going to take a lot more time and money. We ( the controllers ) told them to save the money and spend it elsewhere. The FAA did and FAST isn't really being used in the terminal environment. However, the other parts of CTAS are still alive and well and being put to very good use.

regards

Scott

Okay, big request coming up here.

Is anyone in a position to post a picture of the radar display (or from the Sim) showing a typical pattern on a busy day at LL? It would be such a valuable teaching tool for all of us. If we could then persuade HEATHROW DIRECTOR or his friends to post a few words explaining what is going on, I think we would all get a better insight into how it all works.

I guess that to preserve your identity you might have to ask a "friend" to take the picture, but just think - we will be able to revisit the whole helicopter traffic/cleared ILS debate, the crossing the zone debate and how the stacks are really emptied anti-clockwise discussion - with pictures!!!

I know it is a lot to ask, maybe the training section could help (Mr Chips??).

If we could make this work, I think it would be a feather in the cap for Pprune.

Yours hopefully

G W-H

Hammy - can you PM me dude???