Jump to content

What happens when you put a prop on incorrectly...


Recommended Posts

Sharing my idiocy so someone else doesn't repeat. I flew my new miniplane for the first time with one half of the prop incorrectly fitted, the curved leading edge at the back and sharp trailing edge forward - obvious now but something it was pretty much impossible to do on my previous machine so I overlooked it.

Symptoms were massive lack of thrust and violent vibration in flight. Because I had never flown a miniplane before, I didn't suspect the lack of thrust was due to set up so I persevered and I managed, after a fast run, to take off and get to 100 feet agl into wind, but sank when down wind.

Thankfully, no harm done and second flight was sublime.

Link to comment
Share on other sites

Ooops! Even with a single piece wooden prop, the thrust is reduced to only around 30% when 'reversed'...

I' have to admit I put a prop on wrong way round before too, but spotted it on my preflights...

Moral of the story- If you even suspect that anything is wrong at all, STOP and make sure it's right.

Link to comment
Share on other sites

This is a good reason to manually check prop clearance before starting. When I've fitted the prop, I get hold of each tip in turn and rotate the prop through one full turn, checking that there is clearance to the cage, engine etc. all the way.

A backwards blade won't clear the engine, so it's not possible to start.

This check will also show up errors in cage assembly, sagging engine mounts, things dangling through the netting etc.

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.

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.


  • Upcoming Events

    No upcoming events found
  • Create New...