Heathrow steep approach trials
 

Heathrow Airport has published a timeline for various trials planned for the next couple of years or so and intended "to inform the London Airspace Management Programme (LAMP) consultation".

It includes, starting in February 2015, a trial involving early morning arrivals which will "assess the impact of steeper approaches on arrivals (>3 degrees)".

What are the implications for ATC, given that obviously not all arrivals at that time of day will be suitably equipped ?

Generally, for approaches steeper than three degrees, it's more a case of aircraft certification and approval rather than equipment.

Depends how 'steep' is defined. London City ILS glidepaths are both 5.5 deg and many other UK airfields have ILS glidepaths in excess of 3 deg (Farnborough is 3.5 deg both ends); ICAO definition is 'in excess of 3.5 deg' I think, at least they say a 'normal' GP is from 2.5 to 3.5.
You can only do Cat 11 or Cat 111 approaches with 3 deg.
The flight crews should be aware if the GP angle is anything other than 3 deg, so it shouldn't affect them, after all, the autopilot will fly the GP whatever angle it is.

Yes, I was using "equipped" in the wider sense.

I'm guessing that we'll be talking about TEAMed arrivals between 0600 and 0700, with normal 3° approaches on the other runway.

I suspect that "steeper" in this context will turn out to mean no more than the 3.2° approach listed under "Quieter operating procedures" in Heathrow's recent "Long-term hub capacity options" document.

I'm sure Heathrow Airport will give more details nearer the time of exactly what the trial will entail. Guesses are just that at the moment.

True, they have no place on PPRuNe. :O

Whilst we are all guessing, why would it not be the long hauls pre 0600?

DR UK

Indeed, also as described on Page 25 of this document,


http://www.heathrowairport.com/stati...throw_2013.pdf

Not exactly a Space Shuttle Approach (thankfully) but I suppose an extra couple of hundred feet might make some difference to the likes of the chap on another thread who was worried about flights over his pub......

FWIW we're OK for CAT 2/3 autoland at up to 3.25 degrees but I assume since it's only a trial initially rather than cranking the G/S up :uhoh: we'll be TEAMed and use a "steep" LOC or RNAV approach.

Well you would have to ask Gonzo for an ATC view, but I suspect that:

a) a >3° approach may not be as feasible in a Heavy, compared to, say, a 737/A320

b) LHR operates with a single runway pre-0600 and interleaving steep and standard approaches on the same runway (assuming not all arriving types and carriers are certificated for 3.2°) might well present interesting challenges for ATC (and how would the ILS cope?).

Of course I'm only guessing. :O

> 3 to 3.2 degrees is certainly feasible in a couple of heavies I know of, but would be interesting ( as in almost impossible) in any sort of tailwind and in any event would almost certainly require Full Landing Flap....There's also the (almost universal requirement) to be spooled up to approach power not later than 1000' AAL/ 3 and a bit miles out. With full "draggy" landing flap that will result in a relatively high thrust setting in the final stages of flight compared with the current values that are used when landing using a lower flap setting.

The chap in the mythical pub on 10 mile final may be able to enjoy his early morning beer :hmm: in piece and quiet, but perhaps the residents of Cranford won't be quite so keen.......It will be interesting to see what the trial reveals.

Another interesting snippet with ATC implications, this time from the Appendix to the report dealing with short-/medium-term options:

"Heathrow should begin work with the CAA to build the case for declaring its arrival runways to be independent of each other, removing the dependency between successive arrivals"

Seriously, roughly 120 ft extra at 5 miles is enough to make a difference?
Yes if you're trying to miss obstacles, but for noise????
Talk about clutching at straws.

Maybe they'll change the MLS glidepath and leave the ILS as normal.

Evidently a 5.5% approach for the A380 at the suggestion of Emirates. See here:

AirportWatch | Emirates keen on changing 3 degree approach slope to 5.5 degrees, to allow A380s to land at Heathrow part of the night

That particular proposal didn't go anywhere.

I was told in about 1973/4 that there had been a trial at Dallas for the use of an extremely steep approach angle in order to bring the noise footprint of a B707 to within the airfield boundary ... I'm fairly sure the angle was into double figures!!

In the same seminar, run by Southampton University, we were told of the experiment in which a B707 was used to measure pure airframe noise in fight by turning off all 4 engines (I don't know about the APU). It was only attempted once ... the pilot refused to do it again.:eek:

<<the pilot refused to do it again>>

Spoil sport!

er 5.5% is not the same as 5.5 deg.
Didn't London City originally have 2 segment approaches?

Sorry Chevvron, that was gross finger trouble! I meant degrees. Duh!

But with a 6k long runway as per the Davis Commission a bit of a floater won't be a problem, unless the departing ahead is a tad slow standing the levers up.

SGC