Jump to content

Enstrom question?


Recommended Posts

Its been a long time since I was in one of these, so can someone explain why he waits so long to engage the clutch (about 5:12 in) when the blades are already spinning pretty fast?

 

I always thought the reason for the clutch was to start the engine without having the heavy load of the blades on the engine until it has a chance to speed up?

 

I mean tight belts on a robby will cause them to spin immediately, but the clutch is still engaged right away.

 

Link to comment
Share on other sites

fIvBtDJ.jpg

 

He only waited a couple of minutes after getting the motor turning and warmed up, probably because he was taking extra time to explain the startup for the video. The weight of the drive belt and slight tension on the pulleys will cause the belt will slip and drag a bit even before the clutch handle is engaged, slowly turning the blades (they really aren't turning that fast). Engaging the clutch handle pulls the "Idler Roller" into the belt, fully tensioning it and brings blades up to full RPM.

 

From the Enstrom piston training guide:

 

Belt Clutch Engage System
The clutch engagement lever is mounted at the right side of the pilot’s seat, on the forward side of the seat structure. The clutch lever is used to engage and disengage the belt clutch mechanism, and therefore the rotor drive system.
The engine can be run leaving the belt disengaged without damaging the belt or drive components.
To engage the belt, the engine RPM should be at idle RPM, (1500). Check that the rotors are untied and clear. Engage the clutch handle and slowly begin to lift the handle up. By controlling the handle, drag the engine RPM down into the 1000 to 1100 RPM range and modulate it to keep the RPM in range. When the Blade RPM reaches 100, the clutch can be fully engaged and then the handle stowed.
To disengage the belt, the throttle must be fully closed.
CAUTION
Do not attempt to disengage the belt unless the throttle is fully closed. Serious damage to the engine can result.
Engage the clutch handle and slowly release the belt by pushing the handle forward. Hold the handle tightly so that it cannot spring forward out of control. Push the handle until it is completely down to the floor. The rotor system should slowly decrease until it stops. It is preferable not to disengage the handle after releasing the belt clutch.
(Depending on the tightness and the rubber compound of the belt, the rotor may not completely stop rotating on some helicopters.)
Belt
The Enstrom helicopters use a wide single piece serpentine belt that is wound using a continuous Kevlar cord. There has never been belt failure on an Enstrom helicopter.
Look at the inside ribbing of the belt during the preflight inspection. Small cracks running across the belt ribs are a normal sign of aging. The belt may be continued to operate until pieces of the ribbing are shed that are approximately ¾ inch diameter. The internal cord of the belt should never be visible through the cracks in the ribbing on the inside of the belt.
  • Like 1
Link to comment
Share on other sites

Its been a long time since I was in one of these, so can someone explain why he waits so long to engage the clutch (about 5:12 in) when the blades are already spinning pretty fast?

 

I always thought the reason for the clutch was to start the engine without having the heavy load of the blades on the engine until it has a chance to speed up?

 

I mean tight belts on a robby will cause them to spin immediately, but the clutch is still engaged right away.

 

 

Ahhhh thinking about purchasing an Enstrom!??!?!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...