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Guest chrut

Speed transition, error detected

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Hey!I was practicing high weight takeoffs and of course noticed the speed transistion value chaning from the default 250/FL100 to someting like 275/FL100. This is due to my high takeoff gross weight and is a normal behaviour for the aircraft. But... at the very end of the initial climbout, the aircraft shows illogical behavior. First, let's consult the manual (p. 43 in the FMC User's manual):"Speed Transition: The speed transition is displayed in line 3L. The transition speed/altitude defaults to 250/10000, but will change to reflect a higher performance limit speed of the aircraft if aircraft speed performance is a factor due to high gross weights."If I understand this correctly, the transistion speed is to be followed even though a speed restriction of 250/FL100 exists. During climbout, when flaps 1 is selected, the next speed therefore would be the transistion speed (in my case 278). Instead of this happening when reaching flaps 1, the next speed is pinned to 250. The speed stays there until I select flaps UP. When I select flaps UP, even though the speed didn't increase to pass green flaps indication, the speed bug moves to flap UP position and stays there (in my case flap UP speed was 257. The aircraft then holds speed 257 until FL100, where it accelerates to ECON CLIMB SPD (in my case 333, this is correct behavior though).The aircraft should select speed transition when reaching flaps 1 is selected (as long as isn't above 280 KIAS which is flaps 1 limitation speed) so it accelerates to transition speed (278 in my case). Pictures found below:Here the airplane correctly set the speed to not accelerate above speed restrictionHere the airplane INCORRECTLY set the speed to not accelerate above speed restriction, notice it only goes to 250 KIAS and not directly under the red markingsNow when flaps 1 have been selected, I expect to see the speed to be set to transistion speed 278. But instead the speed settles to 250.The mentionings above are confirmed here, the speed is still 250 and won't change UNTIL I select flaps UP.Here I have selected flaps UP, only then the speed moves. But not to speed transition, to flaps UP speed 257.The aircraft remains at flap UP speed 257 until it reaches FL100

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Hi,You have set a speed "restriction" of 250/10000 at LSK4L, thats why the aircraft restricts to that speed, even if the speed "transition" LSK3L is mutch higher.

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Have you tried clearing the 250/FL100 restriction from the LSK4L?

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No problems here with the speed transition and FS9. Your problem is the speed restriction entry. Remove it and you will see that the a/c goes to the transition speed with flaps 1. Jan-Paul

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Alright, so the SPD/TRANS doesn't have priority over SPD/RES? That's what I thought, alright... good will test this ASAP. Thanks for the help. It would be helpful if any of you could take a look at other threads that I have made.

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Alright, so the SPD/TRANS doesn't have priority over SPD/RES? That's what I thought, alright... good will test this ASAP. Thanks for the help. It would be helpful if any of you could take a look at other threads that I have made.
Update:Well, that did it. Putting in SPD/RES will have prio over SPD/TRANS, thanks!

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