The Buttons below will take you through the different hints and tips that I feel will make your helicopter safer and more reliable.

Oil Tank Cap And Vent


Oil tank cap and vent

Here is an NTSB official report on the crash of an Exec 90 that you may find can save your ship from crashing:

The private pilot stated during a telephonic interview that he was hovering in an open field adjacent to the airport, when he began to lose rotor RPM. He landed briefly to investigate why the helicopter was not flying properly. He then decided to hover taxi back to his hangar and was trying to keep the nose of the helicopter pointed into the wind. While hovering with a slight right crab over a freshly plowed field the helicopter settled, the right skid contacted the soft terrain, and rolled onto the right side. The pilot stated that the loss of rotor RPM was the result of the loose engine oil cap that sprayed engine oil on the main rotor system drive belts.

The helicopter main rotor blades, tail rotor blades, fuselage, and tail boom were substantially damaged. There was no post-crash fire and the pilot reported no injuries. Weather was reported at the time as winds from 020 degrees at 7 knots, visibility 30 miles with few clouds at 7,000 feet and a temperature of 72 degrees.

When you notice that you are getting oil mist or an oily film inside of your engine compartment it may be coming from the oil tank cap. When this occurs you may wish to modify your system by venting the engines breather overboard away from the engine compartment. This can be accomplished relatively simply.

    • You can fabricate or purchase a vented oil cap and hose to carry oil mist overboard and out of engine compartment
Andrew Burr is now manufacturing a beautiful oil tank cap/vapor vent/ dip stick combination as seen above.
To check the oil during your pre-flight you need only to unscrew the dip stick and check your oil level. No need to remove the cap itself until you are ready to add oil.
The photo above shows how Andrew has installed double "O" rings to seal the oil tank tube so that all oil vapors will vent out of the overboard vent hose keeping your engine compartment and belts clean.
Make sure that any vent cap that you install seals snugly inside of the tank vent tube or oil mist will sneak by and still make a mess.


You can order one of the Andrew's new oil caps by sending Andrew an email. Just CLICK HERE



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