How to perform a climb out

[Selbio]

I have been flying an MD-11 for the past few days and I was reading somewhere that after lift off I would need to continue rotation to 15 degrees and the perform the climb out. What do I do at this point? Am I supposed to rotate a few degrees more ?

Thanks in advance,
Selby

[Nexus]

Yeah, an attitude of 15 degrees is quite normal. Usually keep that attitude and a speed of V2+15 or 20 until you reach the acceleration altitude (everything from 1000 to 3000ft agl), this is were flap retraction starts and you need to reduce the pitch in order to pick up speed, or else you'll be very close to stall speed.
When flaps are fully retracted, you can continue the climb by increasing the pitch so it maintans the 250kt limit below 10.000. Never decerase the available engine power if it's not necessary, like obeying hard constraints on a SID.

When passing 10.000ft, decrease the pitch yet again, and set your speed to 3-engine climb speed, I don't know the exact value for that (I'm not the MD11 wiz, CraigL is), but let's just say that you maintain 300kts until reaching mach-crossover altitude, then you'll fly with mach number. (like M.81)

[Selbio]

THanks,

I usually end up decreasing engine power because the aircraft keeps gaining speed and altitude. Maybe it was ascending with a 10 degree pitch or something like that. I'll try the 15 degrees and maybe a couple of degrees more to be able to maintain v2 + 15.

By the way,
I only know that Vr is rotate speed right? What about V1 and V2? That way I know exactly at what speed I need to do the climb out.

[Craig.]

nexus has it down correct.
as for V1 and V2, i am guessing you want to know what they are for and not the speeds. V1 is the point where any emergency is dealt with in the air, its the last point of which you can abort the takeoff, unless in extreme cases you know the plane wont fly. I believe that V2 is the point which wheels should be in the air. but i may be wrong on that

[Selbio]

Thanks a lot,

I just remember about the V1 and Vr and yes V1 is highest speed at which the plane can abort take off.

I will try to find out what that V2 is that way I can add the 15 and 10 to reach acceleration altitude.

I'm glad I'm asking about all these things, I'm sure my take offs will probably be a whole lot better now that I learning about the procedure.

[Nexus]

V2 is the take-off safety speed. If you lose an engine you can still continue the climb and make an emergency landing.
So if you lose an engine you will maintain the v2 speed throughout the climb, whereas you'd climb with a speed of v2+15-25 with all engines functional.

[alansheppard]

If you would like a definition of all the V speeds go to FS Help, click glossary and scroll down to'V- speeds' The IAS values for some of these are, of course, on each AC Kneeboard.

Alan Sheppard

[chomp_rock]

15 degrees? In jets, like the lear and most airliners I climb out at 30 degrees on full power!

[Nexus]

15 degrees? In jets, like the lear and most airliners I climb out at 30 degrees on full power!

Haha, I wanna see the MD-11 who is able to do that at say 90% MTOW?

[chomp_rock]

I'll bet I can do that! I'll post pics of my attempt.

[Nexus]

I'll bet I can do that! I'll post pics of my attempt.

I don't doubt you or your simulation abilities, my comments were more of an indication how un-realistic it is

[Craig.]

The MD11's tail makes any form of low speed handling very difficult, so a slow high pitched climb is inadvisable, this was part of the reason it was never sucessful, that and a lack of range.

[Nexus]

The MD11's tail makes any form of low speed handling very difficult, so a slow high pitched climb is inadvisable, this was part of the reason it was never sucessful, that and a lack of range.

That's what you get when the "dumb" engineers at Douglas decided to mount engine no2 ON the tail, instead of smothly making it a part of the fuselage

*pun intended*


For people not knowing the story: As Craig pointed out: the MD-11 (aswell as the Dc-10) was plagued by bad handling during slow speeds, caused by the relatively small vertical tail (and rudder surface?). Douglas wanted to make the tail higher, but height regulations prevented them from doing so.

The TriStar, similar in design, did not have this problem as the no2 engine is embedded neatly into the fuselage via the use of a an S-duct. So they could aslo make the tail higher - and obstructed!  :)

Nexus82 a.k.a TriStarfanboy

[Craig.]

actually the DC10 never suffered the problem, because the airframe was smaller than the MD11 it didnt require as big a tail, MD really was stuck with the MD11 it was going to be their saving grace. However with the introduction of ETOPS and twin engined aircraft giving equal or better performance, added to the poor handling & poor engine performance, the MD11 was pretty much the end of MD. Boeing decided it wasnt worth correcting the design problems and cancelled the program, and pretty much ending the era or widebody Tri-jets. At least these things will be hauling cargo for many many years.

[Nexus]

Ah, thanks for clearing that up Craig  :)