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Thinking about Mosquito.
Hello everyone, my name is William and I am strongly thinking about buying a Mosquito XET but there are some performance upgrades I was wondering about before I do.

Are there any companies out right now that make aftermarket main rotors?

I would like to go lighter and wider for better HIG/OG, lifting capacity, and high altitude performance.

Something like full carbon-comp rotors that have at least double the surface area.

The helicopters official use (besides being my toy) will be scouting and support for offroad events which generally take place in the mountains at higher-than-average altitudes (I.E. The Sierras). Parts and equipment that it may be used to ferry can get to be a couple hundred pounds and so I need to improve lifting capabilities as well. This would kill two birds with one stone.

As far as I know since the rotor diamiter doesn't change (just the surface area) and the weight should stay roughly the same or be slightly lighter there should not be any safety concerns.

Also, does anyone make an enclosed cabin kit for the Mosquito to drop its Drag?

Thank you for your time everyone and I look forward to your responses.
If you are wanting to use a larger chord with hopes of gaining more lifting ability, you may not be fully informed. Ray Prouty talks about this in his “Helicopter Aerodynamics” VOL. 1 CH 46 Pg 247-248. He talks about the Reynolds number. “Renolds Number is proportional to the chord times velocity. Higher Reynolds numbers result in slightly lower drag coefficients and higher maximum-lift coefficients in the range of typical rotor blades”. He goes on to talk about by doing this and going to far with it will cause tip losses that will nullify any gains brought by the higher Reynolds number. Also, if you go with a longer chord, it would need to be thicker to support the load. 30% of the drag or “power” is profile drag on the average rotor blade. You couldn’t make the blade thinner because it would never hold up to the torsional loading to resist aerodynamic pitching moments the blade will encounter in forward flight. I think you should instead go with a blade twist of 20 degrees or less keeping in mind that most of the blade benefits comes from the first 10 to 12 degrees of twist. In a hover this twisted blade can increase your blade efficiency (Figure of Marit) up to 5%. This may represent about a 20% increase in payload. This all came from whom I believe is the Prophet of helicopter design, Ray W. Prouty.
P.S. Ray Prouty has a volume two out now.
I'll leave the blade talk to those more qualified, but you can get doors for the Mosquito.

Here's a link to the Composite FX website, they're the company that builds the fiber glass bodies.
The performance of the mosquito is pretty amazing already, you would be surprised at the altitudes some guys are already operating at with the piston models, so the turbine should do fine. The one to talk to about the performance and if modifications even need to be made is Dwight junkin, the XET designer, he could tell you real quick. The helicopter is designed for fun, and was never intended for commercial type operations. There is not much space to store things anyway other than the pilot and few very small carry ons. You can get a external cargo pod, but its very big and not designed to haul heavy weight.
Thanks for the responses...

Also, the parts would be sling loaded not actually riding with me so the storage on board wouldn't matter, just the lifting capabilities.

Just to avoid any legal issues, this is a commercial 'like' use, I do it for fun.

As for increasing lift through increasing main rotor area, I could have sworn that when the rotors are pitched it would displace more air per revolution thus increasing drag (and lift). I don't know the terminology for helicopter parts very well yet so I am not sure we are talking about the same thing or not.
Finally managed to find a reference to cord on google and yes that is exactly what I am talking about increasing. As for tip looses from what I read you can counter those with a tapered or swept tip.

Either way I would still need to find a company that makes aftermarket composite rotors.

Thanks for the info btw, I will be ordering that book you mentioned.
Swept tips would help allot but cost allot more. So would "anhedral" tips, which are tips that are swept down instead of back. The new Blackhawks have these. It increases you Figure of Merit is increased about 2% to 4% thus increasing your lift. They do this by keeping wing tip vortices away and down from the rest of the blade. This keeps the flow pattern over the blade smooth by not allowing wing tip vortices from changing erratically its angle of attack. But again, do to centrifugal force; the tips want to get slung to the outside. This requires allot of engineering to ensure the tip would be strong enough to handle this over many hours of flight. This cost allot. Blade twist can be done and made just as easy as a normal blade so long as it is a constant twist which makes the cost close to manufacture as a normal blade. From what I gather from actual owners, which I am not yet, this helicopter is lite enough not to have a problem with wing tip vortices. Remember this, you can increase your lift coefficient and at the same time decrease your drag coefficient. This is done by increasing your figure of merit (airfoil efficiency).

Going to a higher rotor solidity on the Mosquito will not gain you anything unless you are getting near the stall point or are operating at an inefficient area of the lift to drag slope. Because we already operate at a low disc load the operating blade pitch is actually quite low. Increasing solidity of a rotor decreases its efficiency but increases its ability to create lift for a given rotor diameter. Since we are no where near the max lift capability of the rotor increasing solidity will only result in reducing efficiency and the max lift capability of the helicopter.
We now have some pretty slick looking doors that enclose the cabin. Check them out on the Composite FX site. There is a link to it below the menu bar on the left.
So then lift isn't being inhibited by the rotor, but by the actual power of the engine or by the low pitch angles?

I am just trying to squeeze an extra 250lb of carrying capacity out of it in anyway I can... the rotor seemed the easiest way to do this because I know how the physics work there, but I have no idea how to modify a turbine to produce more power.
I think it might be a center of gravity issue or structural. Just think, if you add 250lbs translated to torque, you would need a proportionate amount of Anti-torque. The tail boom was designed with "X" amount of strength in mind that would tolerate "X" amount of flight hours. You would factor in tensile strength vs. fatigue life using most probable conditions and iterations. You should never exceed a designer’s criterion for operations. He had put allot of thought in those numbers and built around it. You can maybe get away with going with something that has less of a stress on an aircrafts design criteria, but never more. More weight is more anti-torque which is more flexing in the tail boom which starts miss-aligning things out of tolerance which fatigues all of the parts in the tail and anything immediately attached to it, which brings its component life down drastically. Believe me, I like the idea that this is an experimental aircraft which I see means experiment, but do so within the designers’ strength criteria in mind. It may be able to withstand it, I don’t know. We know the design is a very successful design. All of the hours from all of the people who own them have proven this. Should you choose to proceed with this idea, you should work with Mr. Uptigrove or at least run it by him to see what he thinks. Helicopters with tail rotors lose 10% to 20% of their engine power from the main rotor because of the tail rotor. Most helicopter tail rotors require about 15% of the total engine power being produced.

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