Rotor System

When you complete your main rotor blades it is natural to want to paint the entire blade to make it look great. Unfortunately the rotor blades are traveling through the air at near the speed of sound and any particles of dust or rain will blast the paint off. The paint will begin to chip back from the leading edge and this disrupts the smooth air flow around the blades that is needed for lift. The smoother the airfoil surface, the less drag and that means less power is required. Your blades will also get covered with bugs when you fly in the summer months and even they will rob your rotor system of needed power. The blade photo below is typical of a main rotor blade on a Rotorway helicopter after around 25 hours or flying.

The blade below is a composite blade that some builders install instead of the factory blades. I have seen several of these blades with air spaces under the gel coat surface that breaks away with use. The hole must then be repaired which changes the balance on your main rotors

The Rotorway main rotor blade below has several hundred hours on it and the paint edges have been sanded back to keep the airflow clean.

The blade below was painted with the first 1 1/4" from the front masked off and polished. The paint line was then carefully sanded to insure that there was no ridge that could be felt with the fingers. If you can feel it, the airflow will be disturbed proportionately. It is important that the skin to spar seam is painted over to protect the epoxy in that area.

Here is a closeup of the same blade.


The photo below was taken during a pre-flight inspecton of a Rotorway Exec 162F while doing flight training. Just one more thing to keep an eye on. It has broken during the last flight. This is also why we leave the covers off during training, so we can find things like this. The cause of this broken spring is not a design flaw but the spring was most likely damaged during installation by the builder.

When I went to a student to provide advanced flight training in his Rotorway 162F that he had been flying regularly I found this cyclic cable control rod end jam nut had backed off. The builder had installed withness seal to show a loose nut but he had not checked this area during his pre-flights and it could have eventually resulted in a loss of cyclic control. Any steel thread into aluminum needs to have some form of locking mechanism to prevent relative movement between the steel and aluminum threads. If movement is allowed the steel can eventually wear the aluminum threads to the point that they can no longer hold the steel fitting and it can pull free causing al loss of control. Check all of your jam nuts on every pre-flight inspection.


In the photo above you can see one of my students using the blade stands that I built for my Rotorway. The supports were bent from 3/4" electrical EMT conduit with 2" ID PVC pipe couplings on the ends that slip over the ends of the skids. The actual blade support is where the conduit pieces cross and are bolted together at the top. I wrapped that area with foam pipe insulation to protect the blades from scratches.

An Eye blolt was inserted into the conduit at the top that a support cable was attached to. I added a turnbuckle to each cable for adjustment, and a plastic coated metal hook on the end of the cable that hooks onto the main shaft. Since this blade support is braced off the skids and main rotor shaft, the ship does not need to be on a level surface and I can easily install and remove the blades by myself. The trick it to get the initial adjustment perfect to hold the rotor blades at the coning angle so that the aligner block bearings will be centered on the rotor hub outboard pitch pin with no pressure. Once the blades are brought up into alignment with the hub pitch pins they will then just slide on or off with very little effort.

I have added several photos of Raymond Butlers main and tail rotor blades that show the leading edges unpainted. We ended up flying through a very strong rain storm for around 20 minutes and the blades looked as good as new since there was no paint for the rain to wear away.



This past year I was flight testing a newly built Rotorway helicopter when one of the NON-ROTORWAY main rotor blades made by SAFARI catastrophicallydelaminated in flight

To view photos of this event CLICK HERE