How much can a 550 lift?

[WhirlingBladesOfDeath]

As I mentioned in my thread below, I maidened my 550 on my loading dock at work. My coworker and I got to talking about know how much it could lift, and I'm not really sure?

My guess is maybe double it's flying weight? With the FP 3700 Evo 25, it weighs in at 4.8lbs, so maybe 10 lbs gross?

Would it be safe to test something like this? If I add 5lbs to the CG on the frame and then try to lift off for a short hover, how much danger of blowing something? Hehe, I'm thinking back to the duration competition they had for the Trex 450 a while back, we could have a dead lift competition too. :)

Not that I would do this, but what would be the best configuration on a Hurri for lifting? I imagine you would want to run the longest blades possible. Since it would just be hover and very gentle FF, could you bolt on some 600mm blades!?!

Cheers,
Jason

[DebianDog]

Well based on me lifting 8 pounds with my Raptor 60 and 15 pounds with my Condor I would guess 4-5 pounds. Not sure if whatever motor your running is up to the task though ;)

Extending the boom and adding larger blades will increase lift but at what cost?

[Phoinix]

I fly my hurricane at 3200 g gross weight. It can lift off with 5000 no problem, but it will develop manouvering problems with 1700RPM. Increasing RPM helps, but flight time comes down drasticlly.

[WhirlingBladesOfDeath]

For the other ignorant American's (like me) I looked up and 5000grams = 11 lbs!!!

Wow, if you can do that at 1700RPM, just imagine what you could do at 2500!

Thanks,
Jason

[Phoinix]

There is only so much a helicopter can lift. Limits are real and perfromance / rpm is not linear. Plus, spinning your blades at 2500 with max load it can lift, either you would burn your ESC or get the packs sweeting like pigs. Nothing i could recommend.

[nubli]

There is only so much a helicopter can lift. Limits are real and perfromance / rpm is not linear. Plus, spinning your blades at 2500 with max load it can lift, either you would burn your ESC or get the packs sweeting like pigs. Nothing i could recommend.

haha.. What I am sure is it will never lift a pig.. not even the smallest pig.. jk

I would say 5000g is the limit, more than that would spell disaster . anyone dare to try and report back here?

[Phoinix]

I'll try TOW of 5000g this weekend. I'll post eagle tree data for reference.

[Pinecone]

Figure a heli can pull at LEAST 3G, then a 3200 gram heli should be able to take off at about 10 KG. It may take close to full pitch and power to do so.

And I am not so sure that 3D moves are pulling more like 6G, which would mean a gross takeoff weight of 20KG. But with little largin of error. :)

[Phoinix]

I a forward fligth you can achive higher disc loading no sweat, you have the ram air passing through the rotor disc. Although, it's a bit hard to keep the g load on helicopters. Lasting for 2-3 seconds isn't a prove of higher disc loading capability.

Another thing is the helicopter hovering, where the power of the motor is the only factor providing enough induced velocity of air through the disc.

Don't confuse these two different things.

[Pinecone]

True, but you can always do a running takeoff. :)

And you get into hover in ground effect and hover out of ground effect. So you may be able to lift off, but not get higher than 1/2 the rotor span or so.

[Phoinix]

Here you go:

OAT = 0°C
wind calm
Blades CF 550 @1630 RPM

Hurricane 550EP = 2630 g
Underslung cargo = 2400 g
_______________________
Combined weight = 5030 g

OGE hover = 2/3 collective ~ 8,5° pitch



http://i97.photobucket.com/albums/l236/BlenderPilot/Show%20and%20tell/Modeli/Hurricane%20550%20Build/DSC04486.jpg


http://i97.photobucket.com/albums/l236/BlenderPilot/Show%20and%20tell/Modeli/Hurricane%20550%20Build/DSC04487.jpg


http://i97.photobucket.com/albums/l236/BlenderPilot/Show%20and%20tell/Modeli/Hurricane%20550%20Build/DSC04488.jpg



I guess it could take 2 kg more, but than the manouvering capabilities would be over the top. Also, the tail would suck way too much power coutering all that masive torque.
Sorry for the lack of eagle tree data, i had problems upgrading the firmware and it has to go back to USA.

[WhirlingBladesOfDeath]

That's awesome! Great job!

Any particular reason you had such a long line from the heli to the "cargo"?

[Phoinix]

Yes, there is a reason behind the longer line. If you have light cargo under the helicopter, you can have shorter rope attached. As the mass starts to travel around the helicopter C.G. it has some effect on the helicopter. The greater the mass, the more effect it has on the helicopter. Thus, if you put the mass under the heli further away it has less effect.


For example:
If the cargo travels 10 cm due to pilot error, on 1 m line, that would mean that the rope would be at 6° angle off C.G., with the 5 m rope, it would be only 1° off C.G. Longer line has less effect of mass debalancing the helicopter.

[mknope019]

Physics 101 lol

[DebianDog]

Yes, there is a reason behind the longer line.


Right! I was going to say that MOST people want to lift a camera of some type and it will be mounted directly to the helicopter. "Dead lifting" weight is one thing but being able to fly around and be a functional helicopter, with the weight, is another. :thumbup:

[Phoinix]

Right! I was going to say that MOST people want to lift a camera of some type and it will be mounted directly to the helicopter. "Dead lifting" weight is one thing but being able to fly around and be a functional helicopter, with the weight, is another. :thumbup:

My point exactly. One thing is lifting, totaly another thing is manouvering with that load.

A helicopter can pull a lot of weight, but than you are running your helicopter at it's very limit. Wind into the wrong side of the helicopter can spell disaster. Manouvering an overloaded helicopter demands great skill. Just like flying a Jetranger at MTOW. You have to think in advance or you will lose your ship.

Another thing that most people forget is with more load, the rotor runs at higher blade pitch which brings more torque. Tail rotor can take as much as 40% of total power. Think about that :D

[mjdee14]

I also figured with the longer line he could drop the load to the ground quickly and still have plenty of height to make corrections. As stated earlier with the short line the shifting load would cause all sorts of problems.

I once watched an Army heli have to drop and A4 shyhawk itr was carrying due to occilations in flight....it was neat to watch it drop from about 1500 ft onto the desert sand.....

[DebianDog]

Tail rotor can take as much as 40% of total power. Think about that :D


Wow I did not know that. Thanks for all your hard work and testing :hug:

[Phoinix]

Hehe, right http://www.helifreak.com/images/smilies/5grouphug.gif

[mjdee14]

For non metric types....it's 5.29 lbs cargo...11.09 lbs auw.