my mate who is a professional pilot, likes moving map GPS in the Biz Jets he flies
Approved GPS units are used in most modern commercial transport aircraft and are often the primary reference by which the RNP is obtained.
No one and I in particular doubts the accuracy of GPS operating in an
approved certified instalation. However, except in special circumstances, there is required to be a crosscheck available of the GPS computed position.
For many commercial aircraft there is two approved GPS, an automatic crosscheck using DME/DME (some aircraft have extra DMEs especially for this sole purpose i.e. readouts not selectable by the pilots) or VOR/DME or LOC/DME. Finally there is the two IRS. In total some 6 items are individually computing the position of the aircraft. Then add to that two pilots with their own raw data crosschecks which makes 7.5 independent systems checking the position of the aircraft.
Why 7.5?........the captain and copilot often have the same raw data sources selected so while they each check them the data could be corrupt for both pilots.
This is why DME stations are going to be retained long after VORs are history. DME DME is the most accurate crosscheck available.
Once again, the issue is not that they did not have the information available to deduce the actual position of the aircraft the issue is that they did not recognise the situation to be something that was not good for them at that time.
This was not a club puddle jumper with 1 vor 1 ils and 1 dme which have been out of calibration for years. This was a well equipped certified large commercial transport aircraft.
Why has the video been made?, why distributed to all professional training organisations? Because everyone recognises the lessons to be learnt from it in respect of
situational awareness, crosscehcking and CRM.
I think tat you will also find that most companies prohibit the use of unapproved handheld electronic devices in the cockpit during flight. That includes the old handheld GPS toys
as well as the DVD player
Regards,
DFC