Hey IFC! I am going to be flying ATL-SEA tomorrow on a Delta B739 and I’ll be at roughly 80% load. I’m planning on taking off runway 26L which is 10007ft long. What takeoff setting would they use in real life? I was thinking either flaps 5 or 10 but I want to hear what you guys think. Thanks!
Note: You may be asking why don’t I use the existing guides on the IFC. No offense to the creators of them, but I found them to be fairly inaccurate with their data and have heard different things from different users.
I’d say it depends on how much power you should apply, which is about 95% N1 (or 90% on the throttle slider) and your Vr and V2 speeds, which are somewhere around 155 knots for Vr and 165 knots for V2 (I think… take my number-crunching with a grain of salt). You should begin rotating 5 knots before Vr, and you shouldn’t be rotating any later than Vr.
I would use flaps 10, and then retract as necessary (and I find necessary to be whatever requires less elevator input, either from you or the autopilot, relative to your trim setting, which I would put around 15%). Flaps 2 isn’t typically used during flight so when retracting flaps I skip from flaps 5 to flaps 1, and vice versa when I’m on approach. Use flaps as needed to gain lift or speed but don’t exceed the flaps limit posted under the gear lever in the cockpit.
I recreated the conditions you’ve listed and taken off with the parameters I’ve given and you’re good to go (for insurance purposes ;))
Also, in a case like ATL-SEA and a load as heavy as 80%, I would climb to FL340 then take it up to FL360 once N1 is a few percent below 80. On your climb and cruise N1 should be at or less than 80%.
All this is assuming you want to fly it as close to as the way the guys fly it in the real world, lmao. Hope this helps.
Just curious, do pilots ever use 10 degrees irl? I’ve it on a couple airliners.net threads, but 5 and 15 are usually the most thrown-around notches. I guess it’s like 5 most of the time, 10/15 when you’re a bit heavy or a shorter runway, and 25 for airports like SNA… Anyone here able to confirm usage of 10?
Adding on I typically use 10 instead of 5 on the -900 to add a bit of tail clearance on takeoff, never really use 5 unless it’s a very light flight