Nose first at 767 POSKY landings

[Guest]

Does anyone have this problem? In my PIC/POSKY merged 767 the front gear always lands before the main gears! The airplane "floats" for some seconds over the front gear then the main gears land! What's going on???Cheers!

[Guest jase439]

I too have noticed a substantial nose-down attitude with the PIC/POSKY combo. I'm not sure it has anything to do with POSKY per se, however. There is too much lift in the flaps - which is also to blame, I think, for the '67's tendency to "float" much too long in ground effect. Even on the TO roll, I rarely - if ever - need Flaps 15 on the roll out - the aircraft wants to pop off the ground at Vr with Flaps 5 even when my TOW demands Flaps 15.You might try tweaking the flap dynamics in your aircraft.cfg file.J

[Guest]

Can't say I've noticed this with the POSKY 767 at all, but DEFINITELY on the POSKY 757 I have noticed it.http://www.nramsey.net/fs2002/767before.jpg 767 above looks ok. The 757 I always land all 3 gear at the same time...and it is nose down during cruise.

[Guest]

Err...POSky doesn't have a 757 yet.If you're landing nose down in any aircraft, you have too much lift. That means you're either too fast or have too much flaps extended for your weight, or both.Matt

[Guest]

Hmmmm it can be it.... I usually land with full flaps at around 175 knots... too fast? Maybe less flaps?

[Guest]

Guess you were right Matt, in a flight from Detroit to Quebec, i landed at Quebec with flaps set to 15 and around 160 knots... perfect landing! Main gears first, nose up... just perfect!Thanks!

[Guest jase439]

...or the flight dynamics are generating too much lift for a given flap setting...;-) Considering VRef30 is about 135 knots: 5-8 degrees nose down at 150 knots, gear extended, at Flaps 15 and 30K lbs of fuel in the tanks seems excessive to me. If one was authorized to land a 67 at Flaps 15 (as Gustavo did), this would probably be an acceptable configuration (and in Gustavo's case, it seems to have worked)...But that only validates the fact that flap lift is excessive. One should not be flying 160 knots (I suppose in an excessive landing weight situation, perhaps this might apply) over the threshold nor landing in a Flaps 15 configuration.

[Guest]

Yeah, you're right. I was thinking of the Mike Stone 757. It flies nose down during cruise.

[bobbyjoh 11]

Hi Gustavok,Since I don't know your fuel situation or the Zero Fuel Weight (ZFW), a landing speed of 160 knots is excessive in the 767. A nominal speed with with about 12,00-15,000 lbs of fuel, flaps 30 over the threshold and ZFW of 284,000 lbs would be 140 knots. Given the scenerio I just described you would float for some time due to the high landing speed you had. Rembember the planes STOPS flying at about 110 knots in the configuration I just mentioned so you have a lot of speed to bleed off at 160 knots.Try your landings a lower airspeed, again the best way to check this is the FMC on the PIC767 which will advise on the Flaps 30 speed.Hope this will help on your technique.CheersBob JohnsonKDEN

[Guest]

Yep, 175 is definitely too fast. I'd try for even slower than 160, with more flaps. See what you can do at around 145, with flaps 25 or so. Exact speeds and settings depend on weight and winds, of course.Matt

[Guest]

In that particular landing I mentioned, my ZFW was 245000 lbs (the usual PIC zfw) and I had about 8% of my both wings fuel tanks... center tank was empty. Anyway, I usually don't follow much of the "book rules" but the 160 knots speed worked fine. Today I tried another landing, but with flaps set to 25 and a speed of 145 knots... the fuel configuration was about the same. I didn't feel much of a difference, the plane landed as smothly as before...Well, I'm slowly getting better in landing this bird, I found out that the secret is knowing when to set flaps and reduce speed...Cheers!

[Guest jase439]

I think between improving your overall technique (with regard to loadout, speed, and flag configuration) and by adding the following line to {Flaps.0} in your aircraft.cfg file:lift_scalar=0.5...you will have significantly better results. The above change will dispense with the intensely nose-down attitude on approach (assuming you are flying no faster than ~VRef+10) and the '67's over-eager desire to leap off the runway at MTOW at Flaps 5 ;-)