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The Dead Side
14th Feb 2013, 13:04
Hi All,

On most 737NG's I've seen, the ground spoilers will deploy to their respective angles, (52/60 degrees, quoted from The Boeing 737 Technical Site (http://www.b737.org.uk/flightcontrols.htm#Spoilers_/_Speedbrakes)) and stay there until selected otherwise.

Ryanair Boeing 737-800 landing at Stansted airport - YouTube


This seems to be the norm except for;

I've noticed on most Thomson aircraft that the ground spoilers extend to a much larger angle than most other 737NG's.

In this video (Jetairfly, but demonstrates the same effect) you can see the spoilers deploy to a much larger angle, but then retracts to what I consider(ed) to be normal, at presumably a speed such as 60kts.

Jetairfly Boeing 737-800 landing at Charleroi from Las Palmas- 16/06/2011 - YouTube


Any ideas why there is a difference in operation between (seemingly) operators, and how this change can be affected from the flight deck.

Cough
14th Feb 2013, 13:48
Have a look for the Boing 737 short-field design package. Kinda a STOL package for the 737...

RAT 5
14th Feb 2013, 15:39
I don't know anything about the B738 STOL package so I ask the question: does the angle of the spoilers really have such an effect on the ground roll? I thought the brakes were the main stopping equipment. They will be working at autobrake setting with either angles. Max autobrake is mighty effective. Does a few more degrees on the spoilers really shorten the distance? It would have to be an extremely short rwy to have a customer option for that. Surely a more effective method would be to have 3rd detent thrust reverse without any reduction in autobraking. If it was that short how far could you go on the next takeoff? Jetairfly fly charters to fairly major airports. Would they really need such an option, if it was available?

Denti
14th Feb 2013, 15:42
On "normal" NGs the flight spoilers only move to 33 or 38° deflection, only the ground spoilers move to 52/60 degrees. On the SFP all spoilers, both flight and ground, will deflect to 60 degrees on landing. Many airlines, especially those serving small warm water airports have opted for parts of the SFP enhancement for their fleet to enable higher performance out of short fields, some didn't take the two position tail skid for example.

Lord Spandex Masher
14th Feb 2013, 15:49
warm water airports

Does the SFP include the maritime add on?

Denti
14th Feb 2013, 16:48
Of course, it was designed for the GOL operation in and out of Santos Dumont (SBRJ). Which is pretty maritime, just lucky for us that it works at all other airports as well, helps us to get into and out of EDDR at MLW for example.

PPRuNeUser0190
15th Feb 2013, 08:20
What I've heard is that the SFP package 1 is almost no extra price, someone with some more inside information will know more.

It's only for the SFP package 2 (hydraulic tailskid) that you pay the big money.

The Dead Side
15th Feb 2013, 10:37
So do you think that Thomson would've fitted it to their 737's due to the relatively shorter runways at destinations in the Greek Islands e.t.c.?