James Drew: USAF still doesn’t know why its Block 1 MQ-9s fail. In: Flightglobal.com. 17. März 2016, abgerufen am 17. März 2016 (englisch): „The US Air Force says it has avoided 17 more MQ-9 Reapers crashes since last April thanks to a backup electrical system that has been installed as a safeguard against a still-undetermined problem with the starter-generator on the Block 1 version’s Honeywell turboprop engine.“