Where to find B777 flaps 15 takeoff speeds?

[jgracin]

Hello! A question from aviation enthusiast.

I have B777 flight manual (Continental) and operations manual and both list only Flaps 5 takeoff speeds. There is no mention of flaps 15 speeds. Why aren't flaps 15 takeoff speeds in those manuals, and how are those speeds determined.

Thanks!

[clifftop]

VFE - Max flap extended speeds

Flaps 1 : 255 KIAS
" 5 : 235 "
" 15 : 215 "
" 20 : 200 "
" 25 : 190 "
" 30 : 180 "

Recommended speeds for flap settings:
flaps 15: <1/2 fuel = 150 KIAS. >1/2 fuel = 160 KIAS

Takeoff: flaps 5, throttle to 1.85 EPR, advance to near 100%, rotate at 153 KIAS, nose to 10 degrees above horizon, Positive climb confirm, gear up. accelerating to 180 KIAS. at 1000ft flaps to 1, accelarate to 210 flaps up.

Flaps 10 and 15 not recommended on take off.

[jgracin]

Clifftop, thanks for answering!


Flaps 10 and 15 not recommended on take off.

I didn't know that, I thought flaps 15 were used regularly when heavy. Very interesting!

Does using flaps 15 perhaps depend on company policy? I think I've seen people mention that they use flaps 15 takeoff in B777.

[Thylakoid]

Jgracin, the B777 does use F15 for takeoff. There is the so-called BLT or the OPT system from Boeing that calculates speeds for takeoff, after you input some basic info. The B777-300 and the ER uses F15 frequently, depending on the weight, RWY length, etc., etc.

[mutt]

Recommended speeds for flap settings:
flaps 15: <1/2 fuel = 150 KIAS. >1/2 fuel = 160 KIAS

Takeoff: flaps 5, throttle to 1.85 EPR, advance to near 100%, rotate at 153 KIAS, nose to 10 degrees above horizon, Positive climb confirm, gear up. accelerating to 180 KIAS. at 1000ft flaps to 1, accelarate to 210 flaps up.

Flaps 10 and 15 not recommended on take off.

Where did you get this from??? Our 777's dont have Flaps 10 for takeoff and Flaps 15 and 20 are standard!

V-speeds are available in the AFM, FPPM, Takeoff chart, FMS, ACARS.

Mutt

[Engineer]

If you have excess to MyBoeingFleet you will be able look at the Boeing version of the 777 FCOM and FCTM. The take off flap settings are 5, 15 or 20 no mention of 10.
In the performance dispatch section of this FCOM only flap 15 runway charts are provided covering the -200ER GE90-76B iaw with JAR requirements(dry and wet runways) plus -200ER Trent 892 and -300 PW4090 iaw with FAA requirements(dry runway only)
Regarding the flap retraction speeds the FCTM states that all speeds are based on Vref 30. Therefore
Flaps 30 = Vref30
Flaps 25 = Vref25
Flaps 20 = Vref30+20
Flaps 15 = Vref30+20
Flaps 5 = Vref30+40
Flaps 1 = Vref30+60
Flaps Up = Vref30+80
Hope it helps :D

[Old Smokey]

Mutt,
Are you using Flaps 20 Takeoffs?, interesting, any particular Field Length advantages. We're using Flaps 15 for standard operations, with, of course Flaps 5 for exceptional cases.

clifftop,

You have my total fascination in the data provided. Where on earth did it come from? Are you sure you're referring to B777? Particularly fascinating the Flaps Up at 210 KIAS, we don't recommend stalling practice on line ops.

Mutt, predictably, has provided the correct source of the Flap 15 data. Send me a PM jgracin if you'd like a few numbers to play with.

Regards,

Old Smokey

[mutt]

Hi there OS.

Boeing used to recommend F20 for takeoffs when the possibility of windshear existed. We questioned them and they offered a NTO for the use of F15, but not F5. I believe they changed the manual after that.

We keep F20 available for some VIP airports with short runways or close obstacles.

Interesting that you use F15 as standard, why? We have 2 schools of thought here, some prefer F15, some F5.

Mutt.

[jgracin]

Thanks everyone for answering! As I said, I have Boeing 777 Operations Manual, dated June 16, 2003. This manual says very little about take off configurations and only has a table of flaps 5 take off speeds, and no such table for or any mention of flaps 15 take offs. I suppose AFM contains that, but it's impossible to obtain/buy it for non-pilots, isn't it?

[Old Smokey]

jgracin,

As requested, a few Flap15° Takeoff speeds for the B777 to play with. The B777-200ER and B777-300 are the RR Trent 884 and 892 respectively, the B777-300ER speeds are for the GE90-115BL engines.

FLAPS 15 V1 / Vr / V2 SPEEDS FOR MAX TAKEOFF THRUST

WEIGHT: B777-200ER: B777-300 : B777-300ER
TONNES
380 : ---/---/--- : ---/---/--- : 175/184/190
370 : ---/---/--- : ---/---/--- : 172/181/187
360 : ---/---/--- : ---/---/--- : 170/179/185
350 : ---/---/--- : ---/---/--- : 167/176/183
340 : ---/---/--- : ---/---/--- : 165/174/181
330 : ---/---/--- : ---/---/--- : 162/171/179
320 : ---/---/--- : 174/183/187 : 160/168/177
310 : ---/---/--- : 170/179/184 : 157/165/174
300 : 159/163/168 : 167/176/182 : 154/162/172
290 : 156/160/165 : 163/173/179 : 151/158/169
280 : 153/157/162 : 160/169/176 : 148/155/167
270 : 150/154/160 : 157/166/173 : 145/152/164
260 : 146/151/157 : 153/163/171 : 142/149/162
250 : 143/147/154 : 149/159/168 : 138/145/159
240 : 139/144/151 : 146/156/165 : 134/142/156
230 : 135/140/148 : 142/152/162 : 130/138/153
220 : 132/137/145 : 137/148/158 : 126/134/151
210 : 128/133/142 : 133/144/155 : 121/130/148
200 : 124/129/139 : 129/140/152 : 117/127/145
Below 200,000 Kg, who cares!

WARNING! - These speeds are for Dry Runway at Full Takeoff Thrust, Derates, Pressure Height, Slope, Clearway, Stopway, contamination (ad nauseum) are NOT considered....:=

Mutt, Airline policy is all-pervading in favour of favouring continued Takeoff Vs Accelerate-Stop, the lower Flaps 15° V speeds ensure earlier achievement of V1, even at the expense of Higher Assumed temperatures to achieve the requisite climb/obstacle performance. We only carry airport analysis for Flaps 5° where some advantage in increased weights may apply, and don't carry Flaps 20° data at all.

This is not to say that I agree with it, as I've said before, I fly the B777 but do P/E work for other aircraft. For the aircraft that I do the work for and write operational policy, the instruction is to use the flap setting conferring the highest RTOW, even if the actual weight is well below the limits for all of the available flap settings. (T'is one of the nice things about having sole autonomy in dictating the operation:E :ok: ).

Regards,

Old Smokey