PJFlysFast From United States, joined May 2006, 459 posts, RR: 1 Posted (1 month ago) and read 970 times:
I was wondering what does it mean when the non flying pilot says "clamp" during takeoff at around 80 knots? What does it do? I only have heard it on aircraft like the MD-11 and MD80 series aircraft and I think it has something to do with the ground spoilers?
Goldenshield From United States, joined Jan 2001, 4062 posts, RR: 13 Reply 1, posted (4 weeks 1 day 22 hours 29 minutes ago) and read 939 times:
Quoting PJFlysFast (Thread starter): I was wondering what does it mean when the non flying pilot says "clamp" during takeoff at around 80 knots?
In what videos are are seeing this? I just did a Youtube search, and found one from Finnair.
I'm not sure about the UK, or even the rest of the world, but typically here in the US, pilots will say something along the lines of "80 knots" by the PNF, and repeating "80 knots," "Roger," or "Check" by the PF. Perhaps this "Clamp" on the Finnish video is their 80 knots airspeed alive check and response?
edit - I just found a Lufthansa video, and they said "80 knots" "Check", so perhaps what you are describing is isolated?
[Edited 2009-11-06 17:16:35]
"I heard that there are rumors on the internets" -- G. W. Bush at the second 2004 debate
JarheadK5 From United States, joined Nov 2005, 206 posts, RR: 1 Reply 5, posted (4 weeks 1 day 18 hours 22 minutes ago) and read 873 times:
As already stated, "Clamp" is a term related to the use of autothrottles.
In the KC-10 during the takeoff roll, the non-flying pilot calls "80 knots", and the FE responds "Power's set" if it is, in fact, set at the computed takeoff power. These are procedural calls.
GLEN From Switzerland, joined Jun 2005, 91 posts, RR: 0 Reply 6, posted (4 weeks 1 day 13 hours 14 minutes ago) and read 837 times:
Quoting PJFlysFast (Reply 6):
I guess it all depends on the SOP of the airline than?
I think so. When I was on the MD11 the PiC had to check ATS in "T/O CLAMP" mode on the FMA, but no call out.
What he had to do is to disconnect the autothrottle in case it would not clamp.
Goldenshield From United States, joined Jan 2001, 4062 posts, RR: 13 Reply 7, posted (4 weeks 1 day 10 hours 6 minutes ago) and read 798 times:
Quoting JarheadK5 (Reply 7): As already stated, "Clamp" is a term related to the use of autothrottles.
It makes sense then, and must be an MD thing. The OP mentions that they do it on MD-80s, but, of my many MD-80 jumpseating adventures, I don't remember them saying it. At least I know what it is now. I was thinking it was a language thing.
"I heard that there are rumors on the internets" -- G. W. Bush at the second 2004 debate
Very interesting video, with a go-around instructed by JFK tower just before reaching the threshold. Wonder whether this was just for prudence since the crew themselves didn't elect to go-around.
The crew was probably mentally already well prepared - they don't seem to very surprised. They just looked how the situation would develop and waited for the eventual command from tower. Can be a question of seconds whether the RWY gets clear or not.
113312 From United States, joined Apr 2005, 417 posts, RR: 1 Reply 10, posted (4 weeks 1 day 5 hours 3 minutes ago) and read 720 times:
This feature exists on all aircraft that have autothrottle approved for takeoff. However, a callout by crews of the mode annunciation is specific to individual airline policy. Some observe but do not call out.
PGNCS From United States, joined Apr 2007, 1455 posts, RR: 10 Reply 11, posted (4 weeks 2 hours 21 minutes ago) and read 614 times:
It's actually displayed "CLMP" on the MD-80/90 series on the FMA in the thrust window (the leftmost FMA window). Provided autothrottles are used for takeoff (which they almost always will be), the FMA will change to CLMP (pronounced, "Clamp") by 60 knots and the autothrottle servos are then depowered for the remainder of the takeoff; they will normally be repowered automatically when VNAV is selected in the climb. This is similar to the functionality of Boeing, although the terminology is different. Although I have never seen it documented, there is widespread belief in the MD-80 community that CLMP stands for "Computer Limited Manual Power" or "Computer Locked Manual Power" depending on who you talk to. One large airline I used to work for did teach that, though, like I said, I can't prove it. Perhaps a former McD person can shed light on the acronym component?
CosmicCruiser From United States, joined Feb 2005, 1734 posts, RR: 17 Reply 12, posted (3 weeks 6 days 23 hours 24 minutes ago) and read 570 times:
MD-11.... no ref is given to any def other than this below
ATS CLAMP MODE
In CLAMP mode the ATS is engaged, but the ATS servos cannot move the
throttles. CLAMP mode is enabled in the following conditions:
• Takeoff mode on the ground and two or more engine thrust commands
are less than 70 percent of the maximum takeoff setting.
• Takeoff mode is engaged and IAS exceeds 80 knots.
• In flight when command input places the throttles in flight idle and
further thrust reduction is required.
Windshear mode after throttles have reached the maximum rated
thrust.
CLAMP mode is annunciated on the FMA.
PJFlysFast From United States, joined May 2006, 459 posts, RR: 1 Reply 13, posted (3 weeks 6 days 2 hours 57 minutes ago) and read 426 times:
Wow guys lots of cool information here! I really appreciate it! I have one more question regarding the MD-11, I know that it has some sort of computer assisted flight controls that you can see on the overhead. I am not sure what the systems name is but I was hoping maybe you of you could shed some light on the subject for me.
Sponsor Message: 
From United States, joined May 2006, 459 posts, 
From Switzerland, joined Jun 2005, 91 posts, 
From Egypt, joined Aug 2007, 584 posts, 
Sponsor Message: 
Printer friendly format
