Position data on the stand

[Groundgripper]

I was on holiday in Madeira the other week and passed some time on the balcony at the airport waiting for the delayed return flight, watching other holidaymakers being hurled skywards on their journeys home (and topping up the tan!). I noticed that each stand had the lat/long of that stand (to the nearest thousandth of a second) and other data painted alongside where the nose of the aircraft would be, easily visible from the cockpit.

I've never seen that before, despite having flown quite a lot over the last twenty years, mainly on business. Is it a common practice - and does it help speed up setting the IN which, I presume, is why it is there?

GG

[BlueEagle]

It is very common to see the Lat and Long displayed somewhere at the stand, often on a post right in front of it. The Jeppesen charts, (or equivalent), will also have the stand co-ordinates published on them so it is a means of crosschecking too.

[Groundgripper]

Thanks for that, BlueEagle - I thought such data would be displayed somewhere, I've just never seen it so obviously before.

GG

[FlightDetent]

Just to make the picture more colourful, FRA used to have a NOTAM saying these blackboard coordinates are not correct (simplified)

FD.

[Tim Zukas]

"I noticed that each stand had the lat/long of that stand (to the nearest thousandth of a second)..."

Thousandth of a minute, you mean?

[avoman]

In Pedantic Mode;
Degrees, minutes and tenths of a minute only I would have thought. This is the maximum resolution possible for manual data entry into the aircraft inertial navigation system.
The onboard Flight Management System usually knows the position of each stand on each airport . So the display painted on the blackboard is a further crosscheck to the Jeppesen and the FMS.
Once the initial starting position is entered correctly the inertial navigation system will calculate the aircraft's position thereafter with impressive accuracy.