PPRuNe Forums - Why do eJ and Go fly at 250kt below FL100?

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- - Why do eJ and Go fly at 250kt below FL100? (https://www.pprune.org/questions/70560-why-do-ej-go-fly-250kt-below-fl100.html)

Why do EZY (and now GOE) fly at 250kts below 10 unless we ask them to fly faster?

Beacause it is an SOP.

Why don't you ask us to fly faster if you want us to!

I know its an SOP and that you will fly faster if asked to, but why do you fly your aicraft differently than most other operators? For instance most other B737's out of GW,KK and LL will increase to about 300kts when given ''No ATC Speed restriction''
Thanks, just being curious.

O&O - this is because easy SOP's demand that we fly 250 below 10 unless specifically instructed by ATC to fly a higher speed.

Why?

A good question :rolleyes:

As far as i'm concerned its a daft SOP. climbing at 250 kts will produce high rates of climb, if the V/S isn't reduced, TCAS TA's and RA's can be produced.
I had some nice gents on the F/deck from LATCC recently, who complained about the Easy SOP, and agreed that acclerating to speeds above 250 reduced rates of climb, as most aircraft would be acclerating below the stacks at BNN, LAM for instance. TA's etc would be reduced in all probabilty.
Obviously turbulence speeds have to be obeyed, when needed.
I believe JMC do the same, please correct me if i'm wrong.

I believe it's to do with minimising the effect of a birdstrike.

Most aircraft I have flown over the last 23 years have had some guideline or other concerning birdstrike risk, although that was normally below 8000'.

EZ decided, about a year or so ago, to raise this to 10000' and introduce it as an SOP.

Don't know if the decision was based on any specific data.

Rates of climb and descent can be adjusted using V/S to eliminate nuisance TA/RAs but, if this is a big issue, why not write to EZ and seek clarification?

EGGW,

Daft SOP you say?
IF you have ever hit a bird(s) at high speed, you might just have a different perspective.

If it is a big enough bird (or a large flock), the results are not pretty...:eek:

In the Boeing manual the speed restriction applies if the window heat is inop as the windows are more likely to break with a birdstrike (less flexible when cold).

Wouldn't the birds find it more difficult to catch us at 300kts? ;)

PS Breaking the SOP can result in disciplinary action from the company!

Most birds above a 1/2 kilo will do plenty of local damage to most aircraft structures (except windscreen} at 300 kts or higher (at the min expect at least a hole) between 250 and 300 kts expect a big dent as min damage.

The engines won't much care as long as they are at climb power or more, but if at reduced power for approach they may have substantially increased the chance of damage downstream of the fan.

Out of interest 250 kts below 10000ft is the law in the US, ATC cannot clear you to go faster end of story!

It is not such a daft SOP for the reasons already mentioned and high speed below 10000ft can sometimes lead to rushed and unstable approaches. Now I know we are all aces but it does happen.

We as a company also have 250kts below 10000ft as an SOP but an SOP is not a restriction. If briefed, requested by ATC, or operationaly makes sense on the day given weather etc, you can fly faster. Question is how much time and fuel do you save? the answer is not very much.

Since the introduction of OFDM folks have tended to be much more measured in the way they operate the aircraft. The passenger just want a smooth ride after all.:cool:

ive always been under the impression that only the military can fly faster than 250kts below 10000' am i wrong?

Sometimes it is nice to be able to go faster to get the height off so as to not to lead to a rushed approach.

A classic example is suddenly being given a left base to 26 at LTN by the helpfull LATCC people, you really do need high speed to get the height off.

(Before I get the usual argument about having to lose the speed when level so there is no advantage to high speed, lets not forget the square rule)

For canberra and others, in the UK Rule 23 is the one that matters for speed.

Quote:

(1) Subject to paragraph (3), an aircraft shall not fly below flight level 100 at a speed which according to its air speed indicator is more than 250 knots unless it is flying in accordance with the terms of a written permission of the Authority.
(2) The Authority may grant a permission for the purpose of this rule subject to such conditions as it thinks fit and either generally or in respect of any aircraft or class of aircraft.
(3) Paragraph (1) shall not apply to:
(a) flight in Class A airspace;
(b) VFR flight or IFR flight in Class B airspace;
(c) IFR flight in Class C airspace;
(d) VFR flight in Class C airspace or VFR flight or IFR flight in Class D airspace when authorised by the appropriate air traffic control unit;
(e) the flight of an aircraft taking part in an exhibition of flying for which a permission under article 61 of the Order is required, if the flight is made in accordance with the terms of a permission granted to the organiser of the exhibition of flying under article 61
of the Order, and in accordance with the conditions of a display authorisation granted to the pilot under article 61 of the Order; or
(f) the flight of an aircraft flying in accordance with the â€˜A Conditions' or the â€˜B Conditions' set forth in Schedule 2 to the Order.

In simple terms, if you are flying in airspace where other pilots may be flying VFR and aren't getting some for of ATC surveillance and traffic information, the limit is 250 kts.

Outdated rules? Yes probaby. A bit too simplistically summarised above? Yes probably, but that's what it seems to boil down to.

250kts below 10.000'!

Canbera:

In answer to your question, you are wrong.

In class A airspace in UK you can fly above 250KIAS below 10,000'. This of course is notwithstanding any other speed restrictions, ATC, etc...

...except of cause Ryanair, who fly above that speed anywhere they like, particularly into Prestwick when they’re late, i.e. OFTEN.

I think the 250 rule dates back to the mid 60's.After two midairs the FAA thought it would enhance the ability to see VFR traffic..:)

FMGC depends how close in you are! You are often better to slow down and config, then use speed. Depends on the day but leaves you better placed for a stable approach, most times. All depends on the day I guess.

As a matter of interest, often the weakest part of the forward structure is not the windscreen, but the fuselage structure immediately above the windscreen- plenty of aircraft (including at least one 737) have had holes punched in the this area due to birdstrike.

Many moons ago, a F/O was killed after a bird entered the structure just above his windscreen...

Personally viewed the damage a large bird can do to a jet transport in Khartoum years ago.
A buzzard was struck by a Boeing 727 at 4000agl, and the bird went,
thru the radome, forward pressure bulkhead, broke the First Officers left leg, went thru the cockpit door, and what was left of him was splattered all over the first class lounge.

The aeroplane was doing 340 KIAS at impact.

Definately not pretty.

The Grim Reaper

If a bird chases me when I'm doing 300kts, and shows the slightest chance of catching up, then hitting it is the least of my worries !!!!!!!!!!!!!!!!!!!!