Skydiving plane pilot reported after reaching what appeared to be the correct location for the skydivers to disembark, the aircraft experienced a GPS map shift. The pilot stated he visually found the correct location. The pilot reported there was military maneuvers in the area.

ACN 2051513 2023-11 Small Transport Penetration of Prohibited Airspace

Part 91

What is ASRS?

The Aviation Safety Reporting System is NASA's voluntary, confidential, non- punitive incident-reporting system, established 1976. Pilots, controllers, dispatchers, and maintenance technicians file reports describing safety- relevant events. NASA de-identifies every report before adding it to the public database. Reports are not investigated by NASA, the FAA, or the NTSB — they represent the reporter's perspective.

Pilot narrative

Verbatim from the de-identified NASA record. First-person account by the reporter. NASA strips identifying details (names, company, specific time); anonymization placeholders are ZZZ, X, Y.

While conducting skydive operations over Dillingham airfield (HDH) using GPS (OBS mode) to navigate to a user waypoint identifying the drop zone, I had a GPS malfunction where my moving map froze while climbing through 6000-8000 ft. MSL the issue corrected itself and GPS seemed to be working normally again. I notified HCF (Honolulu Control Facility) of the issue and that I was unsure if it was my equipment or if the military was affecting the GPS signal since they were in the middle of a military exercise in the area. At some point while turning to intercept the 080 course inbound to the drop zone my GPS was showing me on course and the GPS time, distance and course off set seemed to be indicating normally and outside sight picture looked good as well so I shifted most of my attention inside to ensure I configured the airplane at the right time. Right after I gave the skydivers the green light to jump and a couple jumped, out my moving map suddenly shifted to show me about 1.5 miles south of the drop zone in the restricted airspace R- 3110B. I immediately stopped the rest of skydivers from jumping, made a left turn to exit the airspace, and notified HCF of the issue. I positioned the aircraft back over the drop zone using outside reference only, released the rest of the skydivers, descended and landed normally.

NASA classification — Anomalies

Aircraft Equipment Problem
Airspace Violation
Deviation / Discrepancy - Procedural

NASA classification — Assessments

Contributing Factors / Situations: Aircraft · Airspace Structure · Software and Automation · Environment - Non Weather Related · ATC Equipment / Nav Facility / Buildings
Primary Problem: Ambiguous

ASRS reports are voluntarily submitted, de-identified by NASA, and represent the reporter's perspective. The presence of reports on a topic cannot be used to infer prevalence in the National Airspace System. The authoritative source is the NASA ASRS Database Online at asrs.arc.nasa.gov ↗.