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Elios000
02-21-2011, 02:33 PM
any one thing the 500 could swing some 473mm blades? or would they be to long/heavy?

lankey
02-21-2011, 02:39 PM
I wouldn't use 473mm on a standard 500.... that's quite a bit longer than the stock 425's. You'd end up having to change your gearing, and there will be a heck of an increase in the chance of boom strikes!

Then I'd ask why would you want to?

Elios000
02-21-2011, 02:45 PM
one of the short comings of the 500 has been its heavier then avg rotor disk loading
running a longer blade like a bigger wing would lower the load per sqr in.

and why does any one run longer blades :P 5cm isnt that much really ether well slight less 4.7cm over stock 425D's i run the Edge FBL are 423 but they just came out with a 473 FBL
10cm bigger rotor disk would bring it up to 1m on the dot just about

dannylightning
02-21-2011, 03:03 PM
one of the short comings of the 500 has been its heavier then avg rotor disk loading
running a longer blade like a bigger wing would lower the load per sqr in.

and why does any one run longer blades :P 5cm isnt that much really ether well slight less 4.7cm over stock 425D's i run the Edge FBL are 423 but they just came out with a 473 FBL
10cm bigger rotor disk would bring it up to 1m on the dot just about

i think you are on to a good thing here. if you try this please let us know how it goes.

i would think there would be no problem adding a blade that is only slightly bigger. but i could be wrong..

Elios000
02-21-2011, 03:10 PM
did some quick check might be just a hair to long a 450 or 445 mm blade would be about perfict really wonder why no one makes them in that size
if you could stretch the boom ~20mm they would work hmmm....

im4711
02-21-2011, 03:47 PM
good luck on the 473 mm blades. They are simply way too long.
I run 430 mm blades and not sure why I would go any longer. The main blades and tail blades look pretty close already. It is a 500 and not a 550 size heli you are dealing with. If you extend the tail boom you possibly could do it. However even than you would need to get a stronger motor and with it a different ESC ...

Mike2112
02-21-2011, 09:49 PM
To those wondering why someone would want to do this, because of the flight characteristics. A light disc loading flies so much nicer (of course you may prefer otherwise for whatever reason). I stretched my 450 and would never go back. The 500 (ESP) is a pig and needs a diet IMO.

Mine flies nicely but a set of 450mm blades is what I crave too...just to lazy at the moment to do it. Look at how a mikado logo 500 flies...they are the shit!! Again, preference only. You may want to throw a 400mm flybar on to help speed the cyclic back up with bigger blades if you still have one. I did this on my 500 (Hirobo 390mm FB) and it is MUCH more stable in wind AND quicker on the cyclic.

Try experimenting on a sim...it will then be clear why!:thumbup:

lankey
02-22-2011, 07:38 AM
Most of us knew the 500 has high disk loading before we got the birds. Not saying don't go to 447mm, but certainly expect to have to make modifications as that's a fairly hefty 11.3% increase in blade length.

I'd look forward to a flight report if you did do it.

dannylightning
02-22-2011, 04:41 PM
Most of us knew the 500 has high disk loading before we got the birds. Not saying don't go to 447mm, but certainly expect to have to make modifications as that's a fairly hefty 11.3% increase in blade length.

I'd look forward to a flight report if you did do it.

not every one that gets one of these even knows what disk loading is lol.. i kind of understand it now but i did not have any clue when i got my 500

sarmeneau
02-23-2011, 10:04 AM
I still don't. LOL well, kinda do.

khymlawrence
02-24-2011, 07:13 AM
whats this disk loading? high or light? thanks.

dannylightning
02-24-2011, 09:47 AM
I still don't. LOL well, kinda do.

here is my explination, if a helicopter has really good disk loading it fly's a lot better. if it does not have good disk loading it does not fly as good and i know the disk loading on the 500 could be a little better.

hope that clears it up for every one :rolling

khymlawrence
02-25-2011, 12:36 AM
courtesy of wikipedia..:):)

Disc loading of a hovering helicopter is the ratio of its weight to the total main rotor disc area. It is determined by dividing the total helicopter weight by the rotor disc area, which is the area swept by the blades of a rotor. Disc area can be found by using the span of one rotor blade as the radius of a circle and then determining the area the blades encompass during a complete rotation. As the helicopter is maneuvered, disc loading changes. The higher the loading, the more power needed to maintain rotor speed.[3]
Increasing the weight of a helicopter increases disk loading. For a given weight, a helicopter with shorter rotors will have higher disk loading, and will require more engine power to hover. A low disk loading improves autorotation performance in rotorcraft.[4] Typically, an autogyro (or gyroplane) has a lower rotor disc loading than a helicopter, which provides a slower rate of descent in autorotation.[3]

now i got it....:thumbup::thumbup:

snjbird
02-25-2011, 06:09 AM
Disk loading = float... if your disk load is high the machine will "feel heavy" sluggish stops, slow starts over shoots, But the heli will be more stable in the wind. Lite disk load means hang time and sharper stops, quicker acceleration but more susceptible to wind and turbulence. :thumbup:

Mike2112
02-25-2011, 08:12 PM
courtesy of wikipedia..:):)

Disc loading of a hovering helicopter is the ratio of its weight to the total main rotor disc area. It is determined by dividing the total helicopter weight by the rotor disc area, which is the area swept by the blades of a rotor. Disc area can be found by using the span of one rotor blade as the radius of a circle and then determining the area the blades encompass during a complete rotation. As the helicopter is maneuvered, disc loading changes. The higher the loading, the more power needed to maintain rotor speed.[3]
Increasing the weight of a helicopter increases disk loading. For a given weight, a helicopter with shorter rotors will have higher disk loading, and will require more engine power to hover. A low disk loading improves autorotation performance in rotorcraft.[4] Typically, an autogyro (or gyroplane) has a lower rotor disc loading than a helicopter, which provides a slower rate of descent in autorotation.[3]

now i got it....:thumbup::thumbup:

That is from the FAA rotorcraft flying handbook! Nice. I love the floaty looking helis...they look so great...like UFOs!

whisperdancer
02-26-2011, 01:31 PM
The Trex 500 would benefit the most from 470mm blades.
It always has been a heavy dog.
Unfortunatelly, the small diameter boom doesn't allow the tail to be stretched.

Look at the MSH protos stretch. It flies much bigger than before with only 40mm more on each blade. Although the increase in blade lenght is small, the increase in outer area is very big. The blades are also wider. Same motor, same ESC.

When I had my trex 500 I searched for the stretch possibility, but without any sucess.

mumpas
02-26-2011, 03:09 PM
look here!
http://www.elyshop.com/store/dettview.php?id=13302

Mike2112
02-26-2011, 08:01 PM
look here!
http://www.elyshop.com/store/dettview.php?id=13302

that looks like the answer. now who knows what motor/lipo/pinion, and esc would work best?

Elios000
02-26-2011, 10:03 PM
hmm maybe one for the scopion or if you can find one one of the CC motors and a 14 or 15 thooth

75amp ESC would do it maybe 8S? or to heavy?

mumpas
02-27-2011, 03:19 PM
neumotor kde 1708h/1y n2 battery4s http://www.hobbyking.com/hobbycity/store/uh_viewItem.asp?idProduct=11916
thooth 15t, esc esc cc ice 100

file castel creation ice 100 head speed 2460 2550 2700

mumpas
02-27-2011, 03:25 PM
file cc ice 100 neumotor 8s pignone t15 kit blade 465 sab

lankey
03-09-2011, 02:42 AM
CY will be releasing Radix 450mm FBL blades soon- now I would be happy to try them out when I go FBL!