Free Flight, Free Speech

I'd expect 10kft

ok. 10Kft would be plenty. Gotta check what am I doing wrong.

I'm not saying it can fly that high.... Just that I'd expect it to be able too

Ok I see the problem..... when I started this I made followed the james's specs, "The rotors turn at constant RPM"...... "Roll is induced by differential collective pitch in the left and right rotor systems,"

Now all the way through my creating this flight model I used a much more power rotor motors, as it's a lot easier to work out the control system if you're not having to deal with insufficient lift/power to do the job in the first place. The correct size turbines were fitted days before release, rotor motors de-rated from 8MW each to 2MW, rotor blades redesigned etc...

So James Cameron says this about the turbines... "The power plant consists of two turbine generators rated at 1,970 shp, 1469 kW,"

Problem is these aint big enough, and if I make them bigger then they drink fuel like a fish drinks water and you have 15minutes of flight time.

James Cameron says this about the rotors... "In combat or emergency flight conditions, throttles may be positioned at 120% for extra power, but this puts the blade tips near sonic speed in the Pandoran atmosphere"

Problem here is that at 1770rpm blades are near supersonic in earths atmosphere as it is.... in Pandora's they'll be even closer... but what it does show is that there is some possibility that blade speed can be varied...

So what I'll do is revisit the flight control system and add a +-20% variable blade speed into the damping system, this will take the workload off the blade angle adjust part of it, preventing them from hitting their stops and maxing out the damping,,, at which point you've probably noticed it rolls over onto it's back..

What I'll also do is limit the max rate of climb to "Maximum rate of climb is 545 meters per minute, with full fuel and ordnance load."... as this is also a control system feature and not an actual airframe of power limitation.....

So expect an update.... might take a day or two.... or more.

The bottom line is that James Cameron makes films... It's a fantasy plane and some of the numbers might not stack up when using real physics.... but I'll see what I can do as it does need a greater ceiling height than 4kft

In the spirit of total confession this is the only 'cheat' within this vehicle.. it's within the rotor file and is because of all I've explained above



Simon

bomber wrote:https://drive.google.com/open?id=1AYVRbrP7UzcgJO4mhZ8PEe3CI9MG0tSu

3 updated files for you... you now have a variable pot to control the range of hover vector velocities between 5kts and 35kts... keys i and o
max upward and downwards is 0.5 of the value... and watch out because it'll have a max height at which point it'll run out of roll dampening.

had to update the hud to take this into account and also the flight control system

regards

Simon

Yup
These worked out like a charm

http://www.jafva.com/flight/1208/

bomber wrote:
The bottom line is that James Cameron makes films... It's a fantasy plane and some of the numbers might not stack up when using real physics.... but I'll see what I can do as it does need a greater ceiling height than 4kft

In the spirit of total confession this is the only 'cheat' within this vehicle.. it's within the rotor file and is because of all I've explained above

Code: Select all

   <ct_factor> 2.0 </ct_factor>   
   <cp_factor> 0.8 </cp_factor>

Simon

Yikes. I would preffer not making 4Kft than cheating. You know, J.C. knew what he was doing all along

Anyhow, your thoughts?

bomber wrote:In the spirit of total confession

I did make it 4Ktf on one flight, when I had great distance to make it there,
But vertically? couldn't make it happen

See the vertical and horizontal tracks on this flight to Makkah

http://www.jafva.com/flight/1203/

@Bomber
I confirm:
With great distance I can make it very slowly to 4Kft.
Mountain hoping? Not yet

http://www.jafva.com/flight/1209/

Best,
IH

Have you noticed how she seems to be crabing ?

earlier I said the rotors weren't man enough to do the job and that to remedy this I'd added what I consider to be a cheat...



Look at the plans for the Scorpion



The size of the scorpion is given here..

https://james-camerons-avatar.fandom.co ... on_Gunship

12.2 meters long
8.73 meters wide
3.51 meters high

35ft comes to 10.6 meters...

Later on in the document it says

"The composite triple-blade rotors are 5.49 meters (exactly 16.47 feet) in diameter"

well that don't make no sense as 2 * 5.49 = 10.98 meters wide, a lot less than the 8.73m, and that doesn't include any gap between them.

There is therefore some ambiguity... or down right inaccuracies going on here...

So yeh I had to use a ct_factor... but maybe if this is ever 3d modeled we might wish to see what it would look like with rotors the correct size.

Simon