Speedtape problem

[Guest fjshepherd]

Exactly the second my wheels lift of the gorund and I become airborne on takeoff, the speedtape goes red, like so:http://i147.photobucket.com/albums/r313/fj...erd/prob744.jpgThis happens whatever I do with the flap setting, I configged it properly, any ideas?

[basa 0]

Francis,Why are you using V/S in this phase of flight ?. You are asking your plane to climb at 2300 fpm with a speed of 215 kts (that is a very low speed for a clean configuration when you are loaded with almost 100 tons of fuel)You are only getting 170 kts because you are asking for "too much" (Look at the pitch indicator: 18

[basa 0]

I will explain myself better:The point with V/S is that it has not "speed protection".After the initial climb-out, when you reach the flaps retraction altitude (let's say 1500 ft), you want your plane to accelerate to the clean configuration speed. The way to get that acceleration is lowering the nose, BUT, if you are in V/S mode your plane WILL NOT lower the nose, it will continue trying to achieve the selected vertical speed (it will maintain an excessive pitch-up attitude) resulting in a stall most of the times.FLCH and VNAV, however, DO HAVE speed protection capability.Jose Luis.

[Guest fjshepherd]

OK, firstly, that shot is for illustration of the problem only and has nothing to do with it. Let me go over the problem again. I config properly, set flaps and trim, and as soon as I become airborne, the speed all goes to red, with no audible warning. I rotate normally.

[lefteris 70]

Francis-you still need to post an image of the problem *WHEN* it occurs. That way, we can explain to you what you're doing wrong (or you will have found a bug that we can trace and fix).

[Guest fjshepherd]

I will. Prepare for more screenshots...

[Guest fjshepherd]

http://i147.photobucket.com/albums/r313/fjshepherd/pmdg1.jpghttp://i147.photobucket.com/albums/r313/fjshepherd/pmdg2.jpghttp://i147.photobucket.com/albums/r313/fjshepherd/pmdg3.jpghttp://i147.photobucket.com/albums/r313/fjshepherd/pmdg4.jpgNormal takeoff, speeds and weights all calculated, RTO Brakes set, Packs on, APU off, all the usual stuff, trim set, using the TO/GA button (screw) with a 5% derate, Flaps 20 etc etc etc... No Tailstrike

[Guest Buck Bolduc]

Why 20 degree flaps? Try 10 degree's.Flap relief problem?I use 10 degree flaps and have never had the red tape like yours.

[Guest fjshepherd]

I have tried it with flaps 10, makes no difference.

[downscc 1,327]

I think the problem is the FLCHG mode... the normal climbout procedure is to use VNAV. If you're not going to use VNAV then I believe you cannot use the autopilot for pitch control until after the flap retraction sequence and you're established in a safe climb; at which point you could use FLCHG until the transition altitude. If you don't want to use VNAV then I think you need to use the MCP only for thrust management (TOGA/THR) and LNAV or HDG.

[Guest A32X]

I believe you can use FLCHG SPD mode for departure and engage the autopilot although I'm not sure you'd want to.Paul

[johndrago 4]

>Normal takeoff, speeds and weights all calculated, RTO Brakes>set, Packs on, APU off, all the usual stuff, trim set, using>the TO/GA button (screw) with a 5% derate, Flaps 20 etc etc>etc... No TailstrikePerhaps it's because you have 250kts set in the MCP, rather than the V2 speed from the FMC. The AC can't obtain 250kts at it's current config. I believe (and please correct me), that's this is similar to the 737 putting a flashing "A" in the MCP speed window when the speed is set higher than can be achieved.Not sure, but this is my theory.- John

[Guest D17S]

Hard to imagine how FLCH could be a TO mode. It shouldn't even arm on the ground, at least it wont' on the airplane next door. Check the overhead. I think one of those darn mechanics left one of the air/ground breakers out. Wasn't this the airplane that's been having tilt problems. Bet they were working on that.

[Guest fjshepherd]

Ignore FLCH mode, that doesn't seem to make the difference. I only puot it on because I didn't set the FMC route. I will try another takeoff tonight. Bear in mind these red bars continue throughout the flight in all phases.

[Guest D17S]

Delete and reinstall the airplane. Sure wish we could do that in real life. Actually, come to think of it, sometimes we do. "Sorry to report, but ya'll gotta go get another airplane, chief. This one's too broke." Great sport to watch ops go crazy! Hey, do we get breakers on the new 744? Bummer about the radar.