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Hot Rod
15th Oct 2008, 14:57
Hi.

What if your clean speed is higher than the published speed restriction? Is there any published rule (hopefully available on the internet) that you then can fly your clean speed?

I remember someone told me (?) that really heavy airplanes use their clean speed instead of 250 kt below FL100 during climb.

Also an issue in SSH (Egypt) where it says max 220 kt below FL100 on their SID´s.

411A
15th Oct 2008, 15:18
Either maintain the stated SID speed (with flaps extended) or ask for high speed climb.

Be advised however, SID speed restrictions are published for a definite reason, airspace limitations being one of those reasons.

Todders
15th Oct 2008, 15:52
Do as the chart says doesn't matter what you clean speed is your job is to comply with the chart as that is what ATC are expecting unless they advise you otherwise. Flaps or no flaps that really doesn't matter by all means ask for the restriction to be cleared if you deem it helpfull but sometimes they are there to help you as well as atc like speed restrictions in the climb above fl100 may well be there to help you get above a certain fl quicker so you can get above an airway/flow of traffic so they can hand you over and maybe get you going the right way quicker.

As for SSH well they usually have traffic coming in with you so it's usually a case of burn it in don't hit the mountain and then slpw up as ness. Just tell them what you doing if it's not whats on the plate. Coming out of SSH they just want you up as quickly as poss(so as not to hit the mountain and they can turn you over it before jedda) so if you tell them you will fly 210/220/230 what ever your clean is they wont mind*/notice*

Little off topic but the egyption controlers perform well but they perform like military controlers they expect alittle more from you. They dont mind being told what your doing or how you would like to do it, I find thats the best way to work with them anyways.

perthtrained
15th Oct 2008, 16:02
Exactly as 411A says! If it's a regular destination, have a chat with the local ATC and in my experience they're helpful with allowing clean speed. This info can then be passed on to your colleagues via company notams/port page.

Jumbo Driver
15th Oct 2008, 18:25
When heavy on departure, I have generally found that ATC will accede to a request for (say) min clean + 10 kts contained in the readback, such as "request departure climb 265kt, operational requirement". LHR SIDs actually contain the note: Maximum 250KIAS below FL100 unless otherwise authorised. which invites such a request. I really can't recall any refusal on either this (UK) or the other side of the pond. In the rare occasions where manoeuvrability (eg radius of turn on LHR BUZAD3J/2K) requires a lesser speed, you should be planning a delay in flap retraction anyway.

It is clearly undesirable for a heavy jet to be climbing with flap extended for longer than necessary. Fuel and bank angle restrictions will be the obvious penalties otherwise.

JD
:)

Jumbo Driver
15th Oct 2008, 19:24
What if your clean speed is higher than the published speed restriction? Is there any published rule (hopefully available on the internet) that you then can fly your clean speed?

Hot Rod, further to my last post - and specific to LHR (EGLL) - the following notes from the EGLL AD 2.22 – FLIGHT PROCEDURES (http://www.nats-uk.ead-it.com/aip/current/ad/EGLL/EG_AD_2_EGLL_en.pdf) entry may be helpful to you:

7 Departure Procedures

b Speed Limit: In order to optimise the departure flow and assist in the separation between successive departing aircraft a speed limit of 250kt is applicable unless removed by ATC. ATC will endeavour to remove the speed limit as soon as practicable after departure, using the phrase ‘No ATC Speed Restriction’. Pilots are reminded that this phrase does not relieve the pilot of the responsibility to adhere to the ground track of the Noise Preferential Route, which may require a speed/power limitation.

c If for any reason pilots are unable to comply with the 250 kt IAS speed limit the pilot should immediately advise ATC and state the minimum speed acceptable. If a pilot anticipates before departure that he will be unable to comply with the speed limit he should inform ATC when requesting start-up clearance, stating the minimum speed acceptable. In this case the pilot will be informed before take-off of any higher speed limitation.

JD
:)

Hot Rod
20th Oct 2008, 08:53
Hi and thanks for all your replies.

It does not seem to be any "general rule" to use clean speed as I was hoping for...

And of course you are right in saying that if nothing else is said you have to comply with the restriction. I never had any problem with that in SSH when I have asked for higher speed.

And for SSH all their SID´s and STAR´s are now cancelled and then maybe that speed limitation too?

>>> HESH (SHARM EL SHEIKH INTL) <<<

SID, STAR (RNAV) FOR RWY 22R, 22L, 04R AND 04L SUSPENDED
: NOTAM HE/A0357/08

rubik101
20th Oct 2008, 11:37
Hot Rod, a word of advice;
Don't look on the internet for rules.

SNS3Guppy
20th Oct 2008, 11:54
It's very simple. Request a high speed climb. The rare occasion may arise that ATC won't approve it, but it's rare. I always get a high speed climb.

misd-agin
20th Oct 2008, 14:42
Check the U.S. FAR regs. There's an exception for exceeding 250 KTS if your clean minimum manuevering speed is above 250 KTS.

In the U.S. there is no waiver of the 250 KTS below 10,000 except for emergencies or military a/c(pre approved, we used to fly 300 or 350 KIAS below 10,000 in the IFR traffic flow).

If there are published maximum speeds on SIDS/STARS, absent relief by ATC, you stay configured, if necessary, until past the speed constraint.

SNS3Guppy
20th Oct 2008, 14:50
Check the U.S. FAR regs. There's an exception for exceeding 250 KTS if your clean minimum manuevering speed is above 250 KTS.


That's not exactly what it says. You mean 14 CFR 91.117:

§ 91.117 Aircraft speed.

(a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m.p.h.).

(b) Unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles of the primary airport of a Class C or Class D airspace area at an indicated airspeed of more than 200 knots (230 mph.). This paragraph (b) does not apply to any operations within a Class B airspace area. Such operations shall comply with paragraph (a) of this section.

(c) No person may operate an aircraft in the airspace underlying a Class B airspace area designated for an airport or in a VFR corridor designated through such a Class B airspace area, at an indicated airspeed of more than 200 knots (230 mph).

(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.

747dieseldude
20th Oct 2008, 21:32
Usually, there are 2 cases:
1. The 250/10,000' is the general ICAO/FAA restriction, not specific to the SID or Airport. Then normally you could fly the minimum clean, just let ATC know. "xxx departure, our minimum clean today is 265". You can also ask for "high speed climb" or "high speed below 10" and few were the times I was refused.
Note: In the US you can't ask and you won't get high speed climb, only minimum clean.

2. The speed limitation is specific for the airport or SID. Then there is a specific reason and I would not want to go faster than published. If I really need to I will ask ATC but not exceed it without permission.

FlightDetent
21st Oct 2008, 09:27
The 250/10,000' is the general ICAO/FAA restriction, not specific to the SID or Airport. Then normally you could fly the minimum clean, just let ATC know. "xxx departure, our minimum clean today is 265". You can also ask for "high speed climb" or "high speed below 10" and few were the times I was refused.

Wow. And silly me always thought that for class D the IFR max 250 kt were put in place to enable see and avoid separation to VFR traffic that is only given traffic information with regard of IFR threats. :ugh: Meaning that no ATCO can clear you for faster as simply he has no jurisdiction over the requirement.

FD (the un-real)

SNS3Guppy
21st Oct 2008, 09:57
Class D = 200 KIAS

Denti
21st Oct 2008, 10:38
Only in the US.

FlightDetent
21st Oct 2008, 10:48
ICAO Annex 11, Air Traffic Services

http://img49.imageshack.us/img49/7145/splicaoal8.th.gif (http://img49.imageshack.us/my.php?image=splicaoal8.gif)http://img49.imageshack.us/images/thpix.gif (http://g.imageshack.us/thpix.php)

FD (the un-real)

SNS3Guppy
21st Oct 2008, 10:52
Only in the US.


I know. However we operate everywhere...and we're not going to be exceeding that speed until we're past at least 3,000' above field, which is going to put us out of the ATA and Class D anyway. We don't go past 200, which puts in compliance both ways.

As for below 10,000 and 250; we go for the clean speed, which for us is V2 +100, typically about 265-280 KIAS or so.

FlightDetent
21st Oct 2008, 11:34
Apart form major TMAs I rarely get "C" as soon as 3000, more like FL100 (Germany) / FL195 (UK, France) / FL065 (Netherlands) / FL 95 (Czech, Finland) / FL110-FL195 (Italy). ....

SNS3Guppy
21st Oct 2008, 11:53
Three is out where we start to clean up, not meet other airspace. By the time we climb there, we're generally well away from the airport.