Astraeus to Keflavik

[BALIX]

Here's one that has been puzzling me for a while - why do the Astraeus flights from Stansted to Keflavik cruise at FL280? All other 737 classics seem to cruise at around FL350. I originally suspected it was something to do with RVSM or MNPS but the occasional flight goes at FL320 so it can't be either of them.

Seems to be a waste of petrol to me :confused: :confused:

[Wizofoz]

I would expect it's 'cause they're very heavy! It's a long way for a 737 and they'd routinley be near MTOW. At that weight the most efficient cruise for a 300 is high 20s, low 30s.

I would assume they step-climb down track.

[BALIX]

Hmmm, not so sure about that one. They fly pretty low in the other direction as well and seem in no hurry to climb once they've burned off some fuel.

[gatwickflyer]

Its most likely a speed thing - probably a need to maintain high cruise speed to keep to schedule . If heavy in a 300 , you are unable to cruise at much more than .75 at higher levels , so if you require .76 plus then you must cruise at lower levels.
When operators start new schedules they are often unable to obtain slots that enable them to cruise at Econ Speed. As they become more established better slots become available and lower speeds/higher levels become the norm.

[Bail out]

The reasons are probably

1/ They have elected to fly at Mach .78, which isn’t achieved at higher levels at those weights in the 300.

2/ Below FL285 they are avoiding MNPS airspace, thus the compulsory routes which they would have to oblige with.

This means they are probably flying low, hard, and direct.

May possibly be “ Blue Spruce Routes “

[TopBunk]

LGWflyer

When operators start new schedules they are often unable to obtain slots that enable them to cruise at Econ Speed. As they become more established better slots become available and lower speeds/higher levels become the norm.

Utter cr*p. They may not get the ideal slots at the airports, but once airborne the fact that they are new flights is absolutely irrelevant.

[CrashDive]

In general the B737-300 is not approved for flight in MNPS / Atlantic airspace as its ( normal fit ) single FMC does not provide sufficient 'Actual Navigational Performance' (ANP) to allow it to comply with MNPS’s Required Navigational Performance (RNP) criteria - albeit that a limited number of B737-300's do have an 'alternate' nav system which ergo acts as a second source of navigational information.

Accordingly, as general rule, B737-300's have to remain clear MNPS airspace - including some 'Tango' routes down to the Canaries - which therefore means operating outside of FL285 thru FL420.

That said, some routes such as 'Blue Spruce' routes do allow some alleviation and flight in the higher levels - remembering that the -300 is certified to a maximum of FL370.
This route is typically available between northern Stansted and Keflavik - but this is is not available on the route between Copenhagen and Keflavik.
Thus, on some routes from Northern Europe to / from Iceland, a B737-300 can fly above FL285, but not on others.

W.r.t. operating at lower altitudes. This has the effect of increasing your True Air Speed ( TAS ) because lower altitudes tend to be warmer and ( as MachNo is a function of air temperature ) with a constant MachNo your TAS will be higher than it will be higher up.
Needless to say however, at lower levels and high MachNo’s your fuel consumption will be higher. If you're looking to maintain a schedule time of arrival - and you're not concerned about fuel burn ( and / or somebody else is paying for it ) - then it makes good sense to stay low ( albeit that it's quite noisy in the flightdeck, due windrush, when down low and going fast ); and also, as is said above, you can often achieve a higher MachNo lower down than you can when high ( due aircraft weight, etc ).

Aside - The B737-700, with its up-rated / additional navigational equipment, has sufficient Actual Navigation Performance (ANP) to allow operation in MNPS airspace.

[BALIX]

Thanks for the responses guys. The MNPS limitation is interesting as quite a few aircraft transiting to Iceland have to dip down to FL 280 to avoid MNPS airspace. Most of them, though, prefer to descend at the last minute. Likewise, coming the other way they are quick to request higher levels once they reach Scottish airspace.

I do occasionally see the Flystars at FL320 on the EGSS-BIKF run but hardly ever above that. We never see the BIKF-EKCH run at any level - they tend to miss our airspace completely to save a few quid!

[CrashDive]

BALIX - We do sometimes ( albeit infrequently ) go up higher than FL320, however the flight plan ( as filed ) along with the schedule times typically require that we 'crack-on' a bit ( hence the lower levels ).

That said, any direct routings are always gratefully recieved and we do indeed think the world of all you ATC folks who're keeping an eye on us when we're out over that dark, cold & rough North Atlantic - cheers guys & gals ! :ok:

[PPRuNe Radar]

Flystar 151 was at FL340 Northbound today ... don't tell the Chief Pilot of Astraeus ;)

[Tom the Tenor]

Will the flights to Deer Lake this coming season be with the 737-700s or with the 757?

Were the earlier 737-700s flights from Gatwick ETOPS. How long were the flights and was it out and back same day with the one crew?

The Air Atlanta 737-200s up to Keflavik were the biz!

[Gareth Blackstock]

Doe anyone know when the Deer Lake flights start?

Also, to fly to Deer Lake do you need to be ETOPS rated?

Gaz

[CrashDive]

Deer Lake is intially starting ( 22nd December ) with 737-700's then probably moving over to the 757's in the spring - flights every Wednesday.

The first two route proving flights ( earlier this year ) were non-ETOPS, but all forthcoming flights will be ETOPS ( for both aircraft types mentioned above..... and, Gareth, ETOPS is an approval, not a rating ).

Route time ( when averaged in either direction, and with ETOPS giving a flight distance of 2200 Nm ) is approx 5:00 and, depending upon the time of departure and thus crew duty limits, you can indeed go there and back in a single crew duty day; Indeed it's actually about an hour less than, say, doing an Aswan which, using a single crew, we also do there and back in a day.
That said, there's a suggestion that the crews might be getting a layover in Deer Lake, for reasons more associated with pax handling and connecting flights than anything else.

.... and just in case you're wondering why people would want to go to Deer Lake ?

Here are some of the reasons why: Humber Valley ( main site ) (http://www.humbervalley.com) and Experience Humber Valley ( Uk Portal ) (http://www.experiencehumbervalley.co.uk)

Now just where did I put my fly rod ? :)

[Gareth Blackstock]

CrashDive

It looks like an amazing place and I may even join you in fishing out there!!

Do you know how long the fights will be going on for, is it seasonal or year round? How long will your layover be?

Gaz

[WHBM]

Deer Lake is the airport for Corner Brook, Newfoundland's second city after St Johns. Actually "city" is a bit of a misnomer, as you will find out when you go there - it's a huge pulp mill and an adjacent small town stuck in the middle of forests and mountains, very far from the madding crowd !

Stephenville airport also claims to serve Corner Brook, although it's even farther away (it's a nice long runway absolutely in the middle of nowhere), and presumably it will be the alternate for Astraeus. Gander is a long, long way away and if Deer Lake is closed the highway probably will be as well.

A long-ago Ms WHBM had a brother who worked at the University in Corner Brook, hence the experience. Lot of heavy snow (and icebergs in the sea) in winter, coolish even in midsummer.