FRA T2 gate signs/ markings

[hikouki]

In this photo, you see a sign placed in front of an aircraft listing the aircraft types that could be accomodated at the gate:

http://www.airliners.net/photo/Malaysia-Airlines/Boeing-777-2H6/ER/1731209/M/

I have some questions:
1) How come the aircraft types are displayed this way, whereas at other airports, they are just indicated on the "yellow bars" on the pavement.

2) The aircraft types seem to be grouped by gate category (based on wingspan?). I wonder why the MD-11 was grouped together with the 773 and A346 - it certainly is not anywhere near as long or as wide (wingspan). And isn't the IL96 a little large to be grouped with the DC10, etc.?

[saupatel]

I believe what you see up there is the electronic guidance for the aircraft to park at the correct point on the yellow line. If you read the comments, one person also mentions it

" The lines with aircraft types are part of the aircraft parking guidance system. Each aircraft is different size and pilot seating positions are different with respect to the aircraft nose. By watching the appropriate line until it lines up with the guide the pilot knows when to stop. "

[brianw999]

Just a guess but I think you'll find that this is an electronic visual guide for pilots when taxiing to the gate where ground marshallers are not used. Those using aircraft in the upper group use the upper indicator and those using aircraft in the lower group use the lower indicator. I think it involves a system where two bars or spots converge in from each side. When they overlap the pilot stops the aircraft.
The yellow bars on the ground are for the guidance of ground marshallers to assist them in deciding when to stop the aircraft (when the nosewheel gets to the relevant line for that type of aircraft) so that the jetway can move into line with the door

[hikouki]

Thanks for the replies!

...an electronic visual guide for pilots when taxiing to the gate where ground marshallers are not used. ..

Quite an interesting bit. Never imagined they could do away with those people.

[Peter Kesternich]

The board with the aircraft types is part of the automatic docking system. It's not even electronic. The pilots simply have to visually align a white bar inside the box with the white stripes on the front panel.
As for the aircraft groupings, it has nothing to do with size or wingspan, but with the position of the front wheel in relation to the exit doors, so that the jetways can be connected correctly. Basically, the system does what the marshaller would normally do, tell the pilots when the front wheels are placed correctly on the yellow lines and bars on the pavement. Many big airports have automatic docking systems. It saves manpower (no marshallers needed) and in many cases - like FRA - there is not enough room in front of the aircraft anyway for a marshaller to be seen from the cockpit of a big plane. The nose is just too close to the building.

[saupatel]

It's not even electronic

Just curious, if it isn't electronic then how is it automated ? Is there some mechanical device to control the lines on that board?

thanks
Saurabh

[Peter Kesternich]

No, it's just the way the bar is fixed in relation to the board. As perspective changes, the bar, which is further away from the board seems to be moving. Quite simple actually

[saupatel]

Interesting stuff. I didnt know that .

[WILCO737]

Additional there is a red and green guidance light to check if you are on the centerline. If you see 2 greens, then you are on the line, if you see red anywhere, then you are too far right or left.
Problem is: It is adjusted to the captains seat only, so the FO cannot double check if we are parked correctly. Only the captain can see it the way it should be.

[Foxtrot]

^This brings a question to mind, does it take into account whether or not the pilot has adjusted his/her seat position? Or does it not matter?

[Peter Kesternich]

^This brings a question to mind, does it take into account whether or not the pilot has adjusted his/her seat position? Or does it not matter?

Well - when we are talking about the pilot's seat in relation to positioning the whole aircraft we are talking about centimeters/inches. So that really doesn't matter. The gates have room to spare at either side and the docking system is not really a millimeter precision tool nor does it need to be.