No speed control.

[Julioviana]

Hello.
I work in the Canaries as a radar ATCO. Here the standard speed of 250 knots is up to level 150. But most of the times aircraft can fly faster.
I would like to know how much is no speed for different aircraf and different situations. Also in the climb.
I´ve been several times in fam flights and for instance in an a320 we kept 340 knots util 6000´ (we had an hour delay).
Sometimes I ask a traffic to maintain high speed and that means for him 270 knots at level 100.
Any comments and suggestions are welcome.
Thanks

[dolly737]

Hi Julio,

To me as a pilot, the term „no ATC speed restriction“ just means that I MAY use any speed, higher or lower(!), than otherwise limited by airspace or flight-plan. Sometimes I may choose to fly faster (delay), sometimes slower (turbulence, overtime pay :rolleyes: ). Although used quite often, I believe this phrase will not serve any purpose, unless speed really doesn’t matter.

If ATC wants us to fly a certain speed, why don’t they ask for a SPECIFIC speed??? As you mentioned, there might be a wide range of speeds used due to a variety of reasons which may not be obvious to ATC.

The question: “What’s your maximum speed until FL... / down to ...ft / until xx miles final?” and a subsequent “maintain xxx knots until xxx” will do the trick in many cases. I’m quite confident most pilots will be happy to give you whatever you wish in order to facilitate a fluent sequence, provided they don’t have good reason to object; and if they have any objection, they will politely communicate it.

Now, I’m talking B737 300 through 800 here: During climb and descent our Vmo is 340Kts. That’s the theoretical limit. For me, speeds up to 320 knots, if asked for, will be no problem. It should be apparent, though, that ATC has a good reason for deviating an aircraft from its economic speed schedule (depending on weight, climb/descent above approx FL270 will be at cruise mach number, below in knots, ranging from around 260 to 320).

[Hippy]

Apologies to Julioviana for going slightly off topic, but in reply to Dolly 737...
To me as a pilot, the term „no ATC speed restriction“ just means that I MAY use any speed, higher or lower(!), than otherwise limited by airspace or flight-plan.
I would be careful about how you interperate that phrase.
AIC35/1998 (Yellow 291) 'Airspace Speed Limits' (http://www.fig.dsl.pipex.com/4Y291.pdf) states that "...the phrase 'No ATC Speed Restriction' does not absolve the pilot from the responsibility to operate at speeds that would...comply with the airspace speed limit in Class E, F or G Airspace." (para 3.5)

Don't worry, I believe that you are far from the only one who miss-interperates the phrase, from both sides of the scope. The AIC was published in March 1998 and starts by saying "Recent observations indicate that some general confusion and misunderstanding may exist..." My own observations would suggest to me that 4½ years later general confusion and misunderstanding still exists. I have wittnessed occasions where aircraft descending in Class G airspace have asked "Any speed restriction?" to which controllers, who are not used to working commercial air transport aircraft, have replied "Err, um, nope." In those cases it is obvious that the controller is not aware of the 250kt limit, but maybe the pilot is. More worrying is the transmission "Request high speed" as the aircraft approaches FL100, met with a similar "Err, um, yeah, sure, fine by me." In this case it appears that neither controller or pilot are aware of the regulations. I have wittnessed both types of exchange on numerous occasions. I would say it is time for some more publicity of the contents of AIC 35/1998.

(The above examples happened in UK airspace. I can't comment for other nations although the regulations were implemented by ICAO)
Rgds,
Hippy.

[vector4fun]

In the U. S., ATC can authorize a deviation from most speed restriction rules *except* the 250kt rule below 10,000'. The only exception to that I am aware of is Houston, TX. (IAH) which has a test program that allows more than 250kt. on climb below 10K. This program is NOTAMed. Besides that, some operators of course, notably the military and NASA, are allowed to exceed the limits because of the performance characteristics of their aircraft.

(250 kts would be VERY slow for an F-104!)
:D

[crj-jockey]

I agree with Hippy.
in general there are no spped limits for IFR-flights within A,B and C airspace. In airspace E some countries (for example Germany) authorise ATC to allow higspeed for IFR traffic below Fl100 if traffic permits and safety is not impaired. In real life you only get it during night, as VFR night flights in E are obliged to file a flightplan.

[Smudge's Lot]

If there is "no speed control" given by the controller in the Canaries, then my TUI airline tends to maintain ECON descent speed, (approx 300 knots) until the pilot feels its time to slow down, but Boeing has a limit of a maximum of 313 KIAS below 8000 feet, so it would not be above that once below 8000.
Personally, if it is a nice day/night then once told that no speed control exists, I tend to fly 300 down to 6000 and then start slowing it down.
Got to catch up the delay somewhere:D