FMS SPD

[TC1 0]

Ok, I just purchased the MD-11 and I am working my way through the first tutorial. My question is when do you activate the FMS SPD button that is located on the FCP. After reading and searching the tutorial I found no refereance to when it is approriate activate that button.ThanksTom

[fumap 0]

Simple lesson on basic A/T system in Md-11. First of all, forget anything you learn about Airbus/Boeing systems, that's something different.Firstly, the A/T system is all-in-one with the A/P main system, so they will work very close each other. For deeper explanations, i suggest you to read the system chapter on the autopilot and autothrottle systems. (or maybe the tutorials)Secondly, to arm the A/T before the TO you need to press the big black autopilot that, as linked to both the systems, will arm the A/T and automatically advance the throttles when you will advance them manually beyond 60-65%After TO, you can arm the PROF mode on the FCP, that is the McDonnell Douglas way of VNAV; that button arm both the modes on the A/T system and into the vertical guidance system, setting the preselected values for climb as calculated by the FMC.The FMC SPD button is needed when, for any reason, you want to switch from a manual mode to the FMS calculated one. For example, on approach the FMS is set to 300 knots IAS in PITCH mode, the ATC tells you to decelerate to 250 knots IAS; so, you set the value needed into the speed digital display with the knob and then, you pull it to set that value active in THRUST mode. Then, imagine that the ATC clear the speed limitation and give you a high speed descent, so you will press the FMC SPD button to restore FMC control over the ATS system and the value returns to magenta and to 300 knots IAS.Also, when the autoflight protections come out the FMC modes will be delete and the plane is automatically turn into HI/LO SPEED PROTECTION modes; after the plane is restored on a normal flight position then you can press the FMC SPD to restore the ATS control to the FMC system.That's a nice button to speed up intervention over the ATS panel. BTW, i suggest again you to read about the autoflight into the manual because i don't remember everything and probably i left out something important...(or maybe i've said some great stupid phrases about ATS system...)Cheers,

[FLEX1978 373]

Ok, I just purchased the MD-11 and I am working my way through the first tutorial. My question is when do you activate the FMS SPD button that is located on the FCP. After reading and searching the tutorial I found no refereance to when it is approriate activate that button.ThanksTom

Whenever you want to control the speed yourself, eg ATC want you at 180kts till 5 DME of the ILS, FMS speed may want you at a different speed due to your configuration.EDIT: Paolo beat me to it ;)Regards

[TC1 0]

Thank you both for your help. What I was seeing while using the tutorial 1 was that during the climb phase, after reaching the speed restrictions of the first phase of the TO, my aircraft was climbing but my speed remained the same. If I was between 240/250 kts I think it would have not have been a problem, I would expect to stay in that spped range untile 10,000 ft. But then I reached 10,000 ft and I expected, after having already activated the Auto Fight Mode for the second time, to see an increase in the aircraft speed to match the FMC. After pushing the FMS SPD button everything appeared to have matched up.So what I thing I need to do when I fly the tutorial for the second time is to either activate the FMS SPD Command or increase my speed by selecting a new speed level manually at the time that I press the Auto Flight button for the second time. This would be an additional step in the take-off section found on page 22 of the tutorial.Tom

[mburkhard 23]

So what I thing I need to do when I fly the tutorial for the second time is to either activate the FMS SPD Command or increase my speed by selecting a new speed level manually at the time that I press the Auto Flight button for the second time. This would be an additional step in the take-off section found on page 22 of the tutorial.

No need for those two extra steps. FMS Speed will activate automatically if you activate PROF according the instructions in the tutorial.Cheers,Markus