A recent series of posts (select label "hot wash") on the Cold War Air Museum Blog has been about cleaning the turbine blades on L-39 Bord 107 to lower the engine peak temperature.
We're happy to report that Jon's temperature is now down to 660. Well, actually that's not Jon's temperature, that is his airplane's engine temperature. Even though some of his admirers think Jon is hot, it would be bad if he were that hot, especially since the temperature we are talking about is in Centigrade (Oops, that's Celsius for those of you born in the last half century).
We received a lot of assistance from people telling us how to perform the procedure and we want to thank everyone that contributed! The spray rig Jon made is on the maintenance ladder. A water jug fits perfectly on a drain below the aircraft. How or why they designed for this, we don't understand. But, as our local resident formerly of the Czech Republic likes to say (repeatedly), "Czechs, are very clever people".
Jon checks the patient's output. As 107 came clean, the specimen became progressively clearer.