On Friday, February 22, 2013 10:20:19 AM UTC-8, Matt Herron Jr. wrote:
Latest GPS jamming tests ( https://www.faasafety.gov/files/noti...t_Advisory.pdf ) are mostly scheduled at night, but the week of March 11-15th they are smack in the middle of prime soaring time; 1:00-2:30PM PST. They may disrupt GPS functionality over most of California and Nevada and a good chunk of Colorado during that time.



I have personally seen big holes of 20 minutes or more in my flight logs in the past due to these tests. Anything that uses GPS is potentially affected, and increasingly many of these devices are safety oriented.



Potential issues include;



1) ruined flight logs for contests, OLC, badges, or record flights

2) loss of GPS navigation to safe landing sites or getting home

3) loss of PowerFlarm collision warnings (due to GPS, not loss of 915mhz)

4) Loss of ADS-B warnings (can someone confirm this?)

5) loss of PCAS warnings?



What happens to drones flown by local law enforcement or private sector during this time? Does SSA or AOAP lobby against this testing on our behalf?



Anyone else concerned or annoyed by this???



Matt

PCAS has nothing to do with GPS and is not affected.
TCAS only uses ADS-B in round about ways and should not affect its resolution advisories/RAs.
ADS-B would be affected if the GPS input to the ADS-B data-out transmitter is affected or the GPS input for the receiver/traffic display system is affected (used to calculate its location relative to the other traffic)
But in effect today hardly anybody in a glider uses ADS-B for collision avoidance. PowerFLARM has 1090ES data-in but few gliders or power aircraft today have ADS-B data-out. Most concentrations probably affecting gliders in this broad area might be PowerFLARM equipped gliders able to 'see' 1090ES data-out equipped airliners in busy areas like near Reno, but even there because of the closing speeds the range/warning offered to the glider pilot is probably not that great. And in locations like Reno with busy airline traffic the more important collision avoidance technology is ATC SSR radar and TCAS (both require transponder equipped gliders) and are not affected by GPS issues. that would change in future as ATC relies more on ADS-B 9and if the FAA ever gets away with closing more terminal radar facilities). Yet more of the silliness with ADS-B, all kind of idiotic. At least in these busy areas TCAS remains as an important collision avoidance technology... and a good reason for having transponders in gliders in those areas.