KC10 FATboy

I wish people would stop making stuff up. I've posted this I think four times now in this thread. As noted for importance in the B-777 manuals ...

"Note: When the pitch mode is FLCH or TOGA, or the airplane is below 400 feet above the airport on takeoff, or below 100 feet radio altitude on approach, the autothrottle will not automatically activate."

Larry in TN

Take a look at the speed plot from the DFDR. They went below bug speed just above 500' AGL. By 100' RA they were so slow that recovery was no longer possible. In fact, they applied full power at about 100' above the water.

80ktsClamp

They were in FLCH. Autothrottle wake-up is inhibited 100% of the time in FLCH.

....and that is quite a poor design.

DCA A321 FO

Wow, the A/T have maintained airspeed 100% of the time on the 767 when I have used it (ok I nudge it sometimes to get it started). So you mean to tell me Boeing took a design that worked and made it dangerous?

I have never tried FLCH inside the FAF though.

I was told by an American instructor in Korea that they know their procedures cold. It is amazing that they did not set the derived decision altitude and that they tried to use FLCH and not V/S or VNAV.

I say this because I shot a VNAV (similar to a V/S) approach the other day when the ILS was OTS for the first time in 6 years on the airplane. It was a non-event. In fact, when we saw the ILS OTS on the atis, the other FO and I said, cool, we get to practice a VNAV for real.

Larry in TN

They didn't really "try" to use FLCH. They briefed and began the approach as a V/S approach. The IOE student got confused while trying to correct for being too high (at a little above 1000' AFL) and hit FLCH. When FLCH caused the airplane to start climbing toward the MCP altitude (3,000') he disconnected the A/P inadvertently put the A/T into HOLD by pulling the thrust levers back to idle manually. The IOE instructor either didn't notice or failed to correct the errors.

DCA A321 FO

Looks like they just never got things set up. The flying pilot's buds didn't really help out.

Larry in TN

He was setup for a LOC-V/S approach but got confused, hit FLCH trying to fix it, then got really confused and couldn't recover.

Seems like a LOC-VNAV approach would have been a better plan but that wasn't even brought up during their approach brief. Don't know why.

An IOE student getting crossed up with the automation is a pretty regular occurrence. It's the check airman's job to get him out of it. This guy stayed pretty quiet the whole time. Don't know what he was thinking. By the time the third pilot spoke up it was too late too recover.

beech1980

I always turn the auto throttles off when I turn off the auto pilot. It is re-iterated often during training, IOE and recurrent to do so. Just like flying a big 172...

Thedude

Not on the 777.
Boeing recommends keeping the auto-throttles on when hand flying.

Timbo

I always did that too, in my 12 years on the 757/767, worked great. But when I went to the 777, they were quite adamant about NOT turning off the A/T's, ever, as mentioned above, it's the new Boeing Way. I do keep my hands on top of them, and I do override them at times, either pushing up when getting slow, or pulling back if getting high/hot.

A friend of mine also on the 777 said he did turn off the A/T's once for a visual landing. He said it was the hardest landing of his career!

After he told me that (about 5 years ago), I really started paying attention to exactly what the A/T's were doing in the flare, both on hand flown landings and auto-lands. They almost always come fwd about an inch for a little extra thrust as you round out at about 20'.

I'm pretty sure they are tied into the radio altimeter and VVI, as well as the airspeed, but I'm no Boeing engineer so I'm not sure exactly what they are looking at in the last 100'. It does do some of the smoothest auto-lands I've ever seen though, so it's doing something right!

One thing that will ruin a nice smooth hand flown landing though, is the sudden pop-up of the auto-speed brakes, before all 12 main tires are on the pavement, so on my landings, I usually hold the speed brake handle and let it come back slowly, at about half speed, vs. let it pop up and drop us the last 3'.