PDA

View Full Version : Minimum altitude when late LDG clearance can be expected.


F-16GUY
27th Dec 2014, 08:15
Coming from the military community our rules and regs might differ from the civilian ones. The incident with Ryanairs late go-around decision in Tallinn got me wondering. What does the civilian rules state regarding the minimum altitude for a low approach or a situation where a late landing clearance can be expected. Our rules in the RDAF states that we cannot go lower than 100 feet in both cases.

Watch from 1:45 in this video...

http://www.youtube.com/watch?v=_NU23WIcPeQ

Will be interesting to see if ATC had issued a landing clearance or if the Ryanair crew carried on with their approach a little too long.

NigelOnDraft
27th Dec 2014, 08:25
Regularly get/read back landing clearance @ LHR with the 30'-50' Rad Alt calls in the background.

There is no general rule as the military have... LVPs has a rule, and in general some appreciation of "why" the clearance is late is needed e.g. departing aircraft on the threshold has different considerations (bmi 321 v BA 744) to controller awaiting taking off aircraft getting wheels off, or preceding landing clearing the runway.

safelife
27th Dec 2014, 08:47
My outfit: landing may not be commenced without clearance. Approach ends at 50 ft over threshold, where landing starts.
German outfit ;)

foxmoth
27th Dec 2014, 09:15
It would have been nice to be told to watch from 1:45 in rather than sit watching some boring take offs!:rolleyes:
OK here it was No ATC clearance - and I would say they should have called the GA, but some times it may be nothing to do with ATC, too high, too fast, sudden change in speed due to wind change or something completely different. Certainly in LVPs you can go round from any height before touchdown itself (and you may touch during the GA) and I see no reason for not doing so in other conditions if not required. In fact there are even situations I might consider a GA just after touching down (runway infringment for example!).

F-16GUY
27th Dec 2014, 10:12
foxmoth,

Sorry about that. Guess that’s 1 minute and 45 seconds of your life that you will never be able to get back. :ooh::ooh:

Now, if I can steal a little bit more of your precious time, I will ask you to read my question again, and answer whether there are any civil regulations or company SOP’s that mandate a minimum altitude for a low approach or a minimum that one can proceed to in case a late landing clearance is expected.

I don’t need a lecture on when it is appropriate to initiate a go-around. I now that already.;););)

FERetd
27th Dec 2014, 10:28
foxmoth Quote "It would have been nice to be told to watch from 1:45 in rather than sit watching some boring take offs!"

Sing along with me........ 'Tis the season to be jolly, lalalala la, la la la la.

Basil
27th Dec 2014, 10:41
In the mil we did, of course, have "Land, one on."

jimjim1
27th Dec 2014, 10:49
Link that opens at appropriate time.

https://www.youtube.com/watch?v=_NU23WIcPeQ#t=106

Right click on video and select "Copy video URL at current time".

Or append #t=106 to URL. 106 seconds = 1m 46s.

ChickenHouse
27th Dec 2014, 11:38
How could there be a minimum altitude for such thing ??? Even if you touch ground you can still encounter a gnu in front of you and have to go-around. Ok, a gnu in Tallinn may be unlikely, but a drunk rusky can.

NigelOnDraft
27th Dec 2014, 12:21
In the mil we did, of course, have "Land, one on." As do some civvy airfields inc LHR. However, it is subject to various restrictions that might not be applicable.

I will ask you to read my question again, and answer whether there are any civil regulations or company SOP’s that mandate a minimum altitude for a low approach or a minimum that one can proceed to in case a late landing clearance is expected.Company SOPs will vary - ours have none. My "interpretation" would be the minimum altitude is 0' - depending on circumstances i.e. it was safe and I "understood" why there was a late clearance, I would aim to make the GA call at the latest so that no touchdown would be made. In practice, to me only maybe, that would be to the initiation of the flare / thrust reduction i.e. where I would normally raise the nose slightly and reduce power, that would become add power and raise the nose substantially.

oceancrosser
27th Dec 2014, 13:24
Regularly get/read back landing clearance @ LHR with the 30'-50' Rad Alt calls in the background.

There is no general rule as the military have... LVPs has a rule, and in general some appreciation of "why" the clearance is late is needed e.g. departing aircraft on the threshold has different considerations (bmi 321 v BA 744) to controller awaiting taking off aircraft getting wheels off, or preceding landing clearing the runway.

NoD

We have had this discussion here before about the ridiculous late landing clearances at LHR. Last night in :mad: weather it was quite early, probably at around 150'. Now that UK controllers can say "cleared ILS", should the ever become able to clear consecutive aircraft to land as done in CDG and the US? :ugh:

NigelOnDraft
27th Dec 2014, 13:34
We have had this discussion here before about the ridiculous late landing clearances at LHR. Last night in :mad: weather it was quite early, probably at around 150'. Now that UK controllers can say "cleared ILS", should the ever become able to clear consecutive aircraft to land as done in CDG and the US?I would rather not... the UK requirement to have the runway clear, or "land after", are a defined and shared responsibility.

To shift all the onus to the crew I do not see as enhancing safety. If you or others find a Landing Clearance come too late, then at whatever point you consider safe GA. I do not tend to see LHR issue late clearances without good reason - they just push the rules to the limit. If your limits are more cautious, then play by those ;)

F-16GUY
27th Dec 2014, 14:16
When you issue a clearance for a low approach, what is the lowest height above the RWY you expect the aircraft to descend to?

I find it weird that there is no precise definition of the term low approach. Our definition in the RDAF is not lower than 100 feet and offset to the right of the runway, so as to avoid overflying any aircraft / vehicles / workers on the RWY.

The Ancient Geek
27th Dec 2014, 15:18
I do not tend to see LHR issue late clearances without good reason - they just push the rules to the limit. If your limits are more cautious, then play by those ;)

The problem is too many arrivals and not enough runways. They time the approaches very close to cram them in but it only takes one to miss an intersection and the runway will not be clear.
UK rules require that the runway must be clear, some other places allow landings behind when the runway will be clear "soon enough" which IMHO is not safe practice.

IGh
27th Dec 2014, 17:24
one question posed, was about a CONTROLLER- initiated go-around:
... Question for the ATC controllers ... a clearance for a low approach, what is the lowest height ...? ... no precise definition ... low approach. Our definition ... not lower than 100 feet and offset to the right of the runway, so as to avoid overflying any aircraft ...Seems the thread-starter's questions were focusing on the training-world, asking about a planned "low approach".

At military- airports in USA we could operate with multiple aircraft actually on the same runway -- recall multiple aircraft (4-ship) landing from overhead-pattern, with each man keeping his own "separation" for his roll-out.

But at the joint-use or civil airport, in USA, this issue of "separation" was for the controller's rules -- he might ORDER an airliner to start a G/A!!! at 50Feet AND steep-turn sixty degrees right. [FAA required Recurrent, 1980's taught the other not-a-Go-Around = "Rejected Landing", an easy fly-out, moderate power, moderate pitch.]

EDIT -- Careful: Checking back for the FAA's original AC to airlines, about newly-required "Rejected Landing" instruction for airline- RCT -- Since the early training the words "Rejected Landing" have been HIJACKED several times, and redefined to the new-user's purpose. In USA, controllers hijacked the words, assigning the term to their LAHSO- invention, citing "RLPs" for their LAHSO (http://cf.alpa.org/internet/projects/lahso/cj6newman.htm)-needs. Then later, the Rejected Landing definition mutated again, by 2000, appearing in ALAR Briefing Note 6.2, with a more restrictive definition (after touch-down ONLY).

So VMC at that big, busy, hub-airport (BOS or ORD) are you going to blindly follow the controllers orders?? Nose-up to the FD-Pitch Cmd (in the TOGA-mode)???

Sometimes, after regular anticipation of the late- GO-AROUND command from BOS tower, maybe you just learn to keep your own separation, NO STEEP TURNS at 50-feet: Ya, the controller may lose "separation" -- but no sense in blowing an engine and dinging a wing-tip, when there was no real threat (just a controller's loss-of-separation).

G/A ? Missed-Apprch ? Rejected Landing (http://www.skybrary.aero/index.php/Rejected_Landings) ? Balked-Landing?
or
a Low-Energy Landing Regime (https://www.tc.gc.ca/eng/civilaviation/standards/commerce-circulars-ac0141-1588.htm): below 50Ft w/ Thrust IDLE.

See previous threads about sense-less G/A mishaps:

http://www.pprune.org/tech-log/490737-psychology-shifts-approach.html#post7300787

http://www.pprune.org/tech-log/504138-go-around-higher-than-minimums-2.html#post7607817

The Oslo G/A (http://www.aibn.no/Aviation/Reports/2003-07)

Tatarstan U9-363 / 17Nov2013 (http://avherald.com/h?article=46b9ecbc&opt=0) at Kazan [MAK's rec' for training G/A -scenario where MAP-altitude is close (quick level-off after start of G/A)].

TC offers the best array Landing phase definitions:
15.2 Go-Around, Missed Approach, Rejected Landing, Balked Landing (http://www.tc.gc.ca/eng/civilaviation/opssvs/managementservices-referencecentre-acs-700-700-016-227.htm#s15-2)
and the old
AC 0141 Low energy hazards ... Balked Landing (https://www.tc.gc.ca/eng/civilaviation/standards/commerce-circulars-ac0141-1588.htm)
... An attempt to commence a go-around or balked landing while in the low-energy landing regime is a high-risk, undemonstrated maneuver....One mishap-pilot cited this (quote from that old Advisory Circular) as his justification for NOT doing the G/A:
A320 /31Jan2010 Rwy-Excursion, Veradero, Cuba (http://www.skybrary.aero/index.php/A320,_Varadero_Cuba,_2010_%28RE_HF%29).

Basil
27th Dec 2014, 17:31
he might ORDER an airliner to start a G/A!!! at 50Feet AND steep-turn sixty degrees right.
Well, in my civil transport he'd get the GA . . .

E_S_P
27th Dec 2014, 17:33
Its hard to tell for sure with the angle of the camera, but to me it looked like it might have been that Q400 (which was shown landing beforehand), had only just about vacated the runway - roughly the same time as the Ryanair would have been crossing the threshold.

You can make some strobes out right at the far end of the runway as the camera pans around to show the GA (around 2:02 on the clip).

Skyjob
27th Dec 2014, 17:36
F-16GUY:
I find it weird that there is no precise definition of the term low approach
Not so weird considering airliners do not ever do a "low approach" with passengers on board unless they take part in an air display.
Approaches are always straight in, never offset do a side to avoid A, B or C.
Approaches are continued no further then the threshold, this is usually around 50' but varies due to the exact positioning of the landing distance markers on the runway (50' assumes 305m air distance, equivalent to FAA markers sets, most EU ones are defaulted to 400m, so just over 50' generally would be the case in EU countries, actual TCH can be found in each AIP and on most charts for each runway end).
Approaches that result in a missed approach from such low altitude can on occasion result in the MAIN wheels touching down due to the inertia of the vessel in flight, which needs to be redirected from a 3 degree descent into an ascent by application of thrust which in turn is not instant due to the time it takes to spool up a large bypass ratio engine.

"Land after" clearances depend on airport and again these must additionally be operator approved for the crew to use. When a runway is very long (e.g. 3500m) and the preceding aircraft decides to vacate at the end of the runway, crew on the next inbound are faced with a few options, one is to execute the missed approach. The other, if offered, is to "land after" to ensure stopping is guaranteed within the available runway distance (e.g. 2500m). Perfectly safe if executed properly and briefed in advance.
Several times when on approach in PMI on 24L some commuters (slow Spanish pops at best) vacate at "the end" as this is where they park their vessels, but the trailing aircraft may need to park on the North side of the terminal and has planned to vacate at C1, <1800m, perfectly safe if the preceding aircraft is near the end of full-length of runway available. It is much more problematic to execute a "safe" missed approach from low altitude awaiting landing clearance to be obtained and a parallel departure from 24R taking place, possibly hitting one of the many large migrating birds in the vicinity of the airport on the island taking an engine out in the process.

LNIDA
27th Dec 2014, 18:18
My understanding was not below 100ft without landing clearance?? thats my floor unless its 100% clear that no one else is on the runway and the frequency is blocked by someone else.

lederhosen
27th Dec 2014, 18:20
I have performed a missed approach in a Boeing just above the flare after being told to standby by the tower after reminding them about landing clearance! Almost as good as the Upper Heyford controller (long long ago) asking me to maintain height and position when requesting clearance through their zone in a gliding competition. Mistakes happen, sometimes due to pilots, sometimes controllers, sometimes a mixture of the two (probably more often than not).

PEI_3721
27th Dec 2014, 20:04
I recall a low Trident GA due to an aircraft on the runway; resulting in a short finned Comet !
EGBQ 1960/70’s, VMC, but with Cat 3b training habit the crew continued to the DH - 12ft.

Piltdown Man
9th Jan 2015, 07:39
We don't have a limit and every year, one or two flights land without a clearance. It's not fully Kosher, but given that the crews involved were satisfied to do, I don't think there is a real problem. However, we have many more cases where landing clearances were given but the crew decide not to do so because they are not satisfied with what they saw ahead. Rigid, inflexible rules are best used for planning, not flight execution.

PM