Pilot of an mq-9 aircraft (unmanned aerial vehicle) reported that due to weather conditions and icin...

Attributes
ACN	1356261
Time
Date	201605
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	UAV - Unpiloted Aerial Vehicle
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 50 Flight Crew Total 6000 Flight Crew Type 50
Events
Anomaly	Deviation - Altitude Excursion From Assigned Altitude Inflight Event / Encounter Weather / Turbulence

Narrative:

While returning to base from an operational mission; aircraft encountered high cloud tops; and heavy precipitation in very low temps. Before reaching the clouds formation; crew ran the icing checklist and asked for higher because they could not determine cloud base. ARTCC approved a climb from FL240 to FL280. However; despite attempts to avoid the icing conditions; the aircraft began to accumulate ice and the aircraft lost almost 4;000 feet. Center inquired if crew needed assistance and offered an altitude block once crew explained they were having difficulty maintaining altitude due to the icing conditions on the aircraft. Center approved and the crew maintained fl210b240 until clear of the weather. Once clear of weather; crew continued on without further incident.

Original NASA ASRS Text

Title: Pilot of an MQ-9 Aircraft (Unmanned Aerial Vehicle) reported that due to weather conditions and icing they needed to change altitude in order to maintain flight.

Narrative: While returning to base from an operational mission; aircraft encountered high cloud tops; and heavy precipitation in very low temps. Before reaching the clouds formation; crew ran the icing checklist and asked for higher because they could not determine cloud base. ARTCC approved a climb from FL240 to FL280. However; despite attempts to avoid the icing conditions; the aircraft began to accumulate ice and the aircraft lost almost 4;000 feet. Center inquired if crew needed assistance and offered an altitude block once crew explained they were having difficulty maintaining altitude due to the icing conditions on the aircraft. Center approved and the crew maintained FL210B240 until clear of the weather. Once clear of weather; crew continued on without further incident.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Pilot of an mq-9 aircraft (unmanned aerial vehicle) reported that due to weather conditions and icing they needed to change altitude in order to maintain flight.