Type 4 De-icing Fluid
 

Any other 146/Avro RJ operators out there having problems with type 4 de-icing fluid turning into a thick wallpaper paste substance and clogging up flying controls???

Check your company's SBs or Tech News There was something out about this a few months ago.

Type iv fluid drys out and forms a powder which when soaked again swells up to a much larger volume which can then refreeze inside flying control areas.

Hope this helps. :ok:

Yeah, we've had the same - we try to avoid Type IV but it's all that certain airports use (we also had a problem with PRG using sand on the runway during the winter, but that's a different issue) So every 'A' check we get the engineers up onto the flying controls to rehydrate any residue and then wash it all out.