Originally Posted by
Brain Potter
An external GPS is an uncertified piece of emitting electonic equipment containing a lithium battery.
Not unlike the phones in all the passengers pockets!
Anyhow the Bad Elf units work well in the 787 when placed in the overhead doorway, where there is less shielding.
The following is from the Bad ELf website:-
"For Part 121 and Part 135 operators, our Bluetooth GPS receivers have been successfully tested, approved, and deployed under FAA AC120-76C for own-ship AMM display during taxi operations. At this time, the FAA does not allow own-ship display on portable devices while en-route. However, EFB apps can display range rings and provide map-centering features using Bad Elf GPS receivers while in-flight.
For Part 91 pilots and operators, Bad Elf GPS units can be used during all phases of flight.
For military pilots, all Bad Elf GPS units successfully passed EMI certification and are listed on the USAF Approved Carry-on Equipment List (as of October 6, 2014) for portable electronics. Our receivers are used worldwide by pilots and ground personnel from every branch of the military."
and if you take a look their site...
https://bad-elf.com/pages/airlines#airlineexplore
You will see they are in use in about 50 airlines and by the US military.