B737 Departure Speeds

[pax anglia]

I live not too far from Henton NDB (CPT 3B/4C SID Ex Luton)and Easyjet 737's are a familiar sight.Also seen are 737's from (I believe)British World Airlines.I understand they may be operated on behalf of EZY but their departure speed seems somewhat lower than their colleagues at EZY.Is this simply due to the fact that a different variant of the a/c is involved? Alternatively,is it Company operating procedures?I concede that it is difficult to make judgments from the ground but I would estimate the BWL a/c are 30kts (or more) slower than the EZY 737's.It
would not appear to have anything to do with the 250kt ATC speed restriction as only BWL a/c seem to be affected.

[one.dot.lo]

I don't operate the 737 or fly out of LTN, however a number of factors might effect the apparent speed of the aircraft.

Quite often ATC give the instruction "no speed" on the departure. Some operators prefer to maintain 250 knots max. below FL100, in case of bird strikes, for pax comfort and to keep noise levels lower (both in and outside the aircraft).

EZY, I imagine, are always in a hurry if that terrible docu-soap was anything to go by, and I'm sure that they wind the speed up as soon as possible (mind you so do I!!)

Paintjobs and size of aircraft can also play tricks on the eye. Watch a jumbo jet coming into land, it looks slower than a turboprop. I can assure you it isn't!!

To conclude, I'd suggest there is no difference between the 737 operators departure speed, unless BWL has a particular SOP below 10,000 ft.

Hope this helps! :)

[pax anglia]

one.dot.lo
Many thanks for your response.Just to confuse matters further,the November edition of Airliner World has a photo of a B737 with "easyJet.com" markings along the fuselage and a BWL tail! Have they read my posting and done it on purpose?
Thanks again,
pax anglia