Narrative:

Approximately 20 minutes into our ferry flight with the landing gear extended; we encountered icing conditions picking up light to moderate rime ice; while at FL200. As we were already flying slowly; at approximately 200 IAS; my captain and I discussed our options. The MEA was 20;000 feet; and our limitation with gear down was also 20;000 feet. We decided to call center to see if they could give us vectors off airway to a lower altitude since our indicated airspeed was degrading. ATC gave us a vector off airway and a lower altitude of FL180; to which I started descending immediately to increase airspeed as well as get out of the icing conditions. This worked; within a few moments we were out of the icing conditions and our airspeed returned. No further incidents; we landed safely at our destination airport.we were VFR at the departure airport and arrival airport; and there was no en-route weather forecast on our flight release. We could not have raised landing gear in this circumstance as they were braced with gear locks in the down position for maintenance so they could be inspected upon return to the USA. While we were VFR at our departure airport; and arrival airport; our level of safety would have been greater had the routing also been forecast as VFR.

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Original NASA ASRS Text

Title: A flight crew on a gear down ferry flight at FL200 encounters icing conditions and begins to lose airspeed with max power set. Flight level 200 is the maximum allowable altitude with the gear extended and the MEA for the airway. A vector off the airway allows a descent to FL180 where the ice melts and airspeed is regained.

Narrative: Approximately 20 minutes into our Ferry Flight with the landing gear extended; we encountered icing conditions picking up light to moderate rime ice; while at FL200. As we were already flying slowly; at approximately 200 IAS; my Captain and I discussed our options. The MEA was 20;000 feet; and our limitation with gear down was also 20;000 feet. We decided to call center to see if they could give us vectors off airway to a lower altitude since our indicated airspeed was degrading. ATC gave us a vector off airway and a lower altitude of FL180; to which I started descending immediately to increase airspeed as well as get out of the icing conditions. This worked; within a few moments we were out of the icing conditions and our airspeed returned. No further incidents; we landed safely at our destination airport.We were VFR at the departure airport and arrival airport; and there was no en-route weather forecast on our flight release. We could not have raised landing gear in this circumstance as they were braced with gear locks in the down position for maintenance so they could be inspected upon return to the USA. While we were VFR at our departure airport; and arrival airport; our level of safety would have been greater had the routing also been forecast as VFR.

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.