[Orv Neisingh]

Orv, has anyone ever done a study using string and video to show how the air flows through our ships in a hover and forward flight?  Seems like we could do a lot of useful modifications that would improve cooling.  Experimenting can lead to the issues you experienced.  Graeme has done some interesting stuff in this area, but it seems like we should be able to get more cool air to the engine and radiator without extensive modifications.  

I still can only get about 10 minutes of hover training done for my bride before we reach redline.  I have purchased an electric water pump, but I am not convinced this will fix the problem and this is a big modification to undertake only to find out it didn't fix the issue.  When I hover without any cowl, it seems to stay cooler.  This tells me I have an airflow problem, not a water circulation problem. 

I think before I do the electric water pump, I am going to cut holes in the upper rear cowl to allow more cool air direct to the radiator.  Would be nice to have a study show the airflow rather than experimenting.  But the helicopter has a big EXPERIMENTAL label on it, so....

Tim, when we do hover training we most often leave the rear upper and lower cowling off for better cool air flow. Rotorway experimented with ducts to bring fresh air into the radiator but the ducts and fiberglass manifold were in the way of our pre-flights. They also had the builder fabricated aluminum shields extending from the radiator to the rear tub area with slots around the exhaust. This too proved to not make a difference and they finally eliminated this heat shields from the Talon kits. When students had them on their ships I suggested that they remove them and most did that.