Swisskloten From , joined Dec 1969, posts, RR: Posted (10 years 11 months 5 days 19 hours ago) and read 47812 times:
I know that there are some planes that have programming so sophisticated that pilots can switch on the autopilot and have the plane land itself. Where in the world would this be legal? Why would this be necessary? Although autopilot can make corrections, it's still important to keep an eye on the area in front of the plane so split-second corrections can be made. I'm sure the pilots are doing this and I'm sure they would be dead tired after a 10-hour flight but still, isn't it probably better to make it impossible to activate autopilot to land the plane? Are there any pilots out there who have done this before? I flew into Kloten one time and the fog was so thick that visibility was zero. Even when they touched down, I could not see the landing lights on the strip. Would the crew use autopilot if they felt it necessary in this situation?
Caboclo From United States of America, joined Nov 2004, 203 posts, RR: 0
Reply 4, posted (10 years 11 months 5 days 19 hours ago) and read 47645 times:
It's called a Category IIIC approach. It's designed for when the airport is fogged in. The Cat I approach minimums are 200 foot ceiling and 1800 feet to 1/2 mile visibility, depending on runway lighting. That's the standard ILS approach that all instrument pilots learn in primary training, using basic equipment. Then there is CAT II, and CAT III A, B, and C, each with progressively lower minimums. These obviously require special equipment, special training for the flight crews, and specific authorization for the particular airline. The procedure is to fly the approach on the autopilot down to the minimums, then procede with a manual landing if the field is in sight, with the exception of IIIC which has no minimums and is fully automated. These systems have improved over the years; I read somewhere that the 767 autolandings were pretty firm, but the T7's are much softer.
Philsquares From , joined Dec 1969, posts, RR:
Reply 6, posted (10 years 11 months 5 days 18 hours ago) and read 47601 times:
The thing you have to remember is in modern aircraft, and I will use mine the 744, when you do an auto land there is more than one auto pilot flying. When you have the auto pilot engaged and arm the approach and subsequently intercept the Localizer and G/S, the system has gone through a very intensive self check. If there is any discrepancy, the aircraft degrades it self to either CATII or NO Auto Land.
Here at SQ, the aircraft have to have an auto land every 28 days. It is not uncommon to see them done about once a week. It is a log book entry and is tracked for each aircraft. If the auto land isn't satisfactory, you write it up.
Now if someone could only figure out how to clear the runway and get to the gate with 0/0
FJWH From Netherlands, joined May 2004, 974 posts, RR: 3
Reply 8, posted (10 years 11 months 5 days 16 hours ago) and read 47457 times:
On the 11th of December I was on a BA flight from AMS to LGW.The landing was rough (thus nice). After we came to an almost complete stop the co-pilot (a woman BTW) announced certain things. One of those was: ...." and the plane landed it self".. She also said something more about the auto pilot but I forgot. Anyway the airport was all covered in fog so, obvious why they landed with autopilot.
FlightS in the next 3 months: MSP, PHX, MEM, NCE, TFS, BCN. All round trips from AMS
Mhodgson From United Kingdom, joined Dec 2002, 5047 posts, RR: 23
Reply 9, posted (10 years 11 months 5 days 11 hours ago) and read 47224 times:
I was on an AMM flight in 1998 (AMM761D ALC-BHX IIRC!), on a 757. The pilot announced we would be doing an automatic landing at Birmingham, before explaining it was something they had to do every so often.
No trees were harmed by this message. However, several million electrons were terribly inconvenienced
Philsquares From , joined Dec 1969, posts, RR:
Reply 12, posted (10 years 11 months 5 days 7 hours ago) and read 46911 times:
Just to clarify, you can do an auto land on any runway that has an ILS. We do it all the time. However, to do a CATII or CATIII, then the crew, aircraft and runway have to be CATII or CATIII qualified.
The fail operational on the "glass" aircraft is actually 3 auto pilots. If one fails, then you still have dual autopilot and CATII or no autoland status.
Starlionblue From Greenland, joined Feb 2004, 17430 posts, RR: 66
Reply 15, posted (10 years 11 months 5 days 3 hours ago) and read 45568 times:
The procedure is to fly the approach on the autopilot down to the minimums, then procede with a manual landing if the field is in sight, with the exception of IIIC which has no minimums and is fully automated.
Well, not quite. IIIC is a vision category, not a landing method category. As Philsquares points out, landing with IIIC (0/0 viz) can be done but what is the point if you can't taxi to the gate.
Automated landings can done at all Cats. That is, if you autoland you autoland. You don't take over when the field is in sight. You can very well land manually even without the field in sight at the start of the approach, as long as minimums requirements are met.
And here is some more info (most of it stolen from old posts )
RVR is Runway Visual Range, basically a distance in feet that the pilot can expect to see forward in his airplane.
The ILS equipment at the airport must be certified for it, as well as aircraft type (actually individual aircraft) and crew have to be certified.
Alert Height (AH) is not like a Decision Height (DH) -
At "DH" (obtained from radio altimeter for Cat.II) you have to make a DECISION to land or go-around...
In Cat.III operations, there is no DH... but you have to make a decision to land based on "what you see"... pilots find the DH "decision" very convenient for Cat.II, but did not exist for Cat.III...
So in "pratical operations", the AH is used somewhat like a DH, but is not regulatory. In other terms, we expect to "see the runway" at that point... which is about 50 feet radio altimeter, just about where the runway threshold is located, in Cat.IIIa minimums. In Cat.IIIb, happens at about 35 feet...
Many 747 are equipped for Cat.IIIa operations (not Cat.IIIb), although most of the "Classic" 747s (with 3 autopilot channels) have the LRCU that is required for Cat.IIIb... LRCU = landing roll control unit... keeps the nose wheel on the center line, using the localizer...
"There are no stupid questions, but there are a lot of inquisitive idiots."
Brick From United States of America, joined Aug 1999, 1655 posts, RR: 7
Reply 16, posted (10 years 11 months 5 days ago) and read 44961 times:
Several months ago while on a United flight I heard our flight crew advise ATC that we were going to do an autoland arriving into Denver. It was one of the smoothest A320 landings I have ever experienced...
After the flight I chatted with the first officer. He said at United they have to do one at least once every 30 days.
MD11Engineer From Germany, joined Oct 2003, 14716 posts, RR: 62
Reply 18, posted (10 years 11 months 4 days 23 hours ago) and read 44785 times:
It is callled a flight confidence check, you´ll do an autoland in good weather conditions, to make sure that everything works as it should.
To be certified for CAT 3B approaches, the runway has to certified (ILS and everything), the aircraft, the pillots, the airline needs to have a special CAT 3 maintenance program running, with especially certified mechanics to work on and test the autopilot systems.
During an autoland, depending on the aircraft, there are several autopilots in action, e.g. on the B757 there are three independent autopilots steering the plane in parallel, each with it´s own sensors (IRU, ILS receiver, radio altimeter, air data computer...) and outputs (each has it´s own servo for each of the primary flight controls. From 1500´ AGL down, the busses will split and each autopilot will have it´s own independent power supply. Together with the autothrottle computer they´ll fly the plane until touchdown and runout. Braking will then be done automatically with the auto speedbrakes system and autobrakes, only the thrust reversers and flaps will have to be operated by hand. The autopilots also crosscheck each other.
The MD11 uses two flight control computers (FCCs), but each box has two seperate channels, which control each other. Each FCC has it´s own power supply, as well as independent inputs and outputs.
Spare parts have to be CAT 3b certified, this means especially bench tested. After maintenance on the autoland system, the whole system has to be checked and tested by a certified mechanic to upgrade the airplane to CAT 3b s
FrndlySkys777 From United States of America, joined Apr 2000, 25 posts, RR: 0
Reply 19, posted (10 years 11 months 4 days 21 hours ago) and read 44541 times:
Like everyone else said above, an autoland is legal. Another factor why pilots don't use the autoland all the time would be to maintain "currency." I know in the US that Federal Air Regulations state that pilots must perform landings on their own every so often. Airlines may also choose to adapt tougher standards. Thus the reason why autolands don't occur often.
In fact in my logbook there is acutally a section where you record the number of landings you make.
Jeb94 From United States of America, joined Oct 2004, 640 posts, RR: 4
Reply 20, posted (10 years 11 months 4 days 21 hours ago) and read 44498 times:
Correct me if I'm wrong but isn't Cat III a crew certification? Thus, a different pilot and F/O combo, though either or both might be Cat III certified, aren't authorized for Cat III approaches as they aren't certified as a team. I've worked for two airlines, neither being Cat III certified, the 1st was Cat II and the current is only Cat I.