Minimum speed during an ILS approach

[LevelMind 1]

Hello,

If there's a speed stated at a ILS charts, for example: "MNM 160KT until D4", should I always fly that speed no matter if ATC tells me or not?

I've also got to scenarios:

1) Let's say we're cleared on a normal ILS approach with no stated speed restriction by ATC, do I still need to fly minimum 160kts until 4 dme, or is it only valid if ATC told me "ABC123 speed 160kts until 4 dme"?

2) If ATC, during the vectoring into the ILS, gave me a couple of speed restriction, let's say, 210kts, and then i get cleared for the approach, do I still fly 210kts until they tell me otherwise (or i ask them), or do i reduce by myself to 160kts since it's stated in the charts?

[MarkW 1,490]

Usually you fly the charted restriction unless told otherwise by ATC.  If ATC gives a speed of 210 they should follow with another speed.....ie 170 to fix or cancel the restriction.  If they don't I think you should ask. 

[LevelMind 1]

Ok thanks,

So if I understand correctly; in a scenario at which you recieved "ABC123 no ATC speed restrictions" or something similar to that, it would only cancel your current speed restriction (or the max 250kts below FL100) and not the charted restriction for the approach?

 

[ESzczesniak 128]

The speed restriction is part of the ILS approach as published.  So if you are cleared for the ILS approach, i.e. "ABC123, cleared for the ILS RWY X, maintain 2,000 until established, contact tower at the marker", you would fly 160 kts until D4. 

The only time you would not fly that restriction is if you got a clearance that said "ABC123, cleared ILS RWY X, no speed restriction,...". 

As for cancelling a current speed restriction, that would be a separate instruction from the approach clearance.  Something like "ABC123, cancel speed restriction".  It would be uncommon to cancel the 250/10k restriction on approach.

Additionally, if you get something like "ABC123, cleared visual RWY X", you are not flying the published ILS procedure and would not have a speed restriction.  You may have tuned the ILS in your aircraft for back up and be flying off of that, but your cleared procedure is not the ILS and the speed restriction would not apply. 

[Guest]

As above.

The speed restriction applies (and implies) "until established" - at which point (i.e: as soon as you ARE established) you would fly approach speeds down the ILS according to your calculations or those of the FMC/ MCDU of your aircraft if on A/P.

Hope that helps.

[ESzczesniak 128]

1 hour ago, ganter said:

As above.

The speed restriction applies (and implies) "until established" - at which point (i.e: as soon as you ARE established) you would fly approach speeds down the ILS according to your calculations or those of the FMC/ MCDU of your aircraft if on A/P.

Hope that helps.

I'm not certain I'm correct on this (i.e., my apologies if I have a misunderstanding), but I'm not sure that being established immediately clears you to your approach speed.  It is common for ATC to give commercial traffic restrictions such as "maintain 170 kts to the marker/FAF".  You can be established (i.e., on LOC, on GS, descending, on LOC CRS) well before the marker.  In fact, legally, you must be established by the time you cross the FAF.  I think if there are any speed restrictions either given by ATC or the approach plate, those supercede anything about being established. 

[bic 44]

O how exciting, there was one time where an American Airlines pilot on JFK 13L or Right was told to maintain 210 knots during the approach and the pilot got into a huge argument with the controller stating that he would miss the airport again (on his second approach) if he did that.  If I recall, the controller stopped arguing with him and just stated to keep his speed up.

Years  ago, Newark controllers told pilots to "maintain 190 knots or better" during the approach clearance.  As a passengar, I remember landing sometimes at what seemed like higher than normal speeds.  Also, I have heard ATC state "plan minimum time on the runway" so they can keep things moving.  Again as a passengar, I remember them getting off the ruwnay ASAP.  From my ATC class, one runway on a clear day can do 60  (or is it 90) operations an hour with ideal pilots.  With some airports, ATC have to constantly be on the ball to keep them moving.  

 

[Guest]

2 hours ago, ESzczesniak said:

I'm not certain I'm correct on this (i.e., my apologies if I have a misunderstanding), but I'm not sure that being established immediately clears you to your approach speed.  It is common for ATC to give commercial traffic restrictions such as "maintain 170 kts to the marker/FAF".  You can be established (i.e., on LOC, on GS, descending, on LOC CRS) well before the marker.  In fact, legally, you must be established by the time you cross the FAF.  I think if there are any speed restrictions either given by ATC or the approach plate, those supercede anything about being established. 

You are right. In RW situations, busy airports and lots of arrivals, with traffic fore and aft the controller might request you to maintain a certain speed in order to maintain separation. But, as a rule, you'll maintain that speed until GS, after that, speed is YOUR decision, based on YOUR calculations - if you're following the traffic in front down to the threshold then, of course, you've already allowed for that separation maintain of approach speed; "Speedbird 4245, Follow the 747 on final"...

If you're unable to follow ATC speed restrictions you tell them: "Unable 160 Knots", etc.

As always, it's a fluid situation made more complicated by local weather, amount of traffic and any NOTAMS in operation at the time. For the purposes of simulation one should follow speed restrictions as far as the Outer Marker and then follow ILS as computed onboard. If that is contrary to ATC pressure/ traffic/ conditions, then a Missed Approach procedure should be rapidly prioritised. After all, it's not your fault.