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OBIO
November 21st, 2009, 15:04
I have spent about 5 hours today trying to get a flight dynamics package together for Joe Binka's G44A Widgeon....the radial powered one. The FDE for the Lycoming R-680 radials is fine....I am trying to get the Pratt and Whitney R-985 radial one going. I have the engine specs altered in the config file...and the increase in power is there...but I can't get the plane to fly for squat.

Is there anyone who actually KNOWS how to work with flight dynamics willing to take on the task of creating a FDE for the Widgeon, powered by 2 450hp Pratt and Whitney R-985s?

OBIO

Lionheart
November 21st, 2009, 15:26
...........runs and hides...


Airfiles are 'verrrrrrrrrrrrrrrrrrrrrrrrrrrrrrry' difficult to work with.. eeks!





Bill

expat
November 22nd, 2009, 06:21
I have little FDE experience or knowledge but it sounds like there may be issues with the maximum speed and aerodynamics using the 450 hp powerplants.

OBIO
November 22nd, 2009, 06:39
I have little FDE experience or knowledge but it sounds like there may be issues with the maximum speed and aerodynamics using the 450 hp powerplants.

In the worlds of Spanky McFarland: AND HOW!

Z-claudius24
November 22nd, 2009, 07:49
Hi,

OBIO .. I guess you use also AirEdit ?
Sometime it's necessary to modify the air file ...
Just a guess in the dark :)

OBIO
November 22nd, 2009, 07:58
I have pretty much every tool for adjusting flight dynamics you can think of...but I don't have the knowledge or the skill to do it. I got lucky on the Pander S.4....Lady Luck isn't paying me any attention when working on the R-985 Widgeon.

OBIO

Willy
November 22nd, 2009, 08:08
I'm assuming you're working with Air Wrench?

Sparks did a Widgeon that's available at his mudpond site.

OBIO
November 22nd, 2009, 08:25
AirEd, Air Wrench, Canned Air, Cheese Wiz and Chili Peppers. I have thrown everything I can at this project and struck out on each attempt.

I suppose the Lycoming R-680 radials will just have to do. The plane has plenty of performance like that....but the thought of having 900 horsepower on tap in a plane whose max weight is less than 5000 pounds...that would be some serious get up and go.

I had the power there, just couldn't tame it. Take offs were amazingly short.

OBIO

Milton Shupe
November 22nd, 2009, 08:45
Can you upload the aircraft folder for this version, send me the physical specs for the aircraft and this engine's performance. and I will take a look at it. I need vspeeds as well.

EDIT: Okay, Henry is on it ... I'll pass and continue to work on the AT-11. :)

Henry
November 22nd, 2009, 08:52
AirEd, Air Wrench, Canned Air, Cheese Wiz and Chili Peppers. I have thrown everything I can at this project and struck out on each attempt.

I suppose the Lycoming R-680 radials will just have to do. The plane has plenty of performance like that....but the thought of having 900 horsepower on tap in a plane whose max weight is less than 5000 pounds...that would be some serious get up and go.

I had the power there, just couldn't tame it. Take offs were amazingly short.

OBIO
i have a problem with Cheese Wiz also
it makes the flaps gunky:icon_lol:
i am a bit tied up for free time at the moment but i will take a look
H

OBIO
November 22nd, 2009, 09:00
Can you upload the aircraft folder for this version, send me the physical specs for the aircraft and this engine's performance. and I will take a look at it. I need vspeeds as well.

The vspeeds are one of the problems I am having. I have no clue as to how much faster the Widgeon would be with an extra 300 horses on tap. The Radial Widgeon powered by two Lycoming R-680 300 hp radials has really good performance....but being a muscle car guy at heart, I know that there is no replacement for big displacement...ie, pull out a little motor, stuff in a big one.

I could find no information at all on the Widgeon with the Pratt and Whitney R-985 radials. Therefore, I have no idea how much weight to add to the empty weight of the plane due to the larger and heavier engines, how much weight to add to the max gross weight with the assumption that more horses equals more cargo capabilities. No idea how much faster the Widgeon would be with 900 horsepower compared to the 600 horsepower with the Lycoming radials. A lot of speculation is in order.

I added 200 to the empty weight, 800 to the max weight (200 to account for the engines, 600 pounds extra carrying capacity) and attempted to add 30 mph to the max speed. I found that with these settings, the plane oversped like crazy, had a horrible nose up problem, and would stall at the drop of a hat....sometimes a wing can only carry so much weight I suppose.

OBIO

Henry
November 22nd, 2009, 09:50
ok thats the Goose engine
i do find that acm gives grief if its the last thing you use
the figures i have for the v max are 203 mph@sea level
i will take a further look
check your pm's
H

Z-claudius24
November 22nd, 2009, 10:06
Hi,

Well .. if the Wikipedia specifications are credibles ....



[edit (http://en.wikipedia.org/w/index.php?title=Grumman_Widgeon&action=edit&section=8)] Specifications (G-44A)

Data from {name of first source}



General characteristics

Crew: one, pilot
Capacity: 5 passengers
Length: 31 ft 1 in (9.47 m)
Wingspan (http://en.wikipedia.org/wiki/Wingspan): 40 ft 0 in (12.19 m)
Height: 11 ft 5 in (3.48 m)
Wing area: 245 ft² (22.8 m²)
Empty weight: 3,189 lb (1,470 kg)
Loaded weight: 4,500 lb (2,041 kg)
Max takeoff weight (http://en.wikipedia.org/wiki/Maximum_Takeoff_Weight): 4,500 lb (2,500 kg)
Powerplant: 2× Ranger L-440C-5 (http://en.wikipedia.org/wiki/Ranger_L-440) inverted inline 6-cylinder engines, 200 hp (150 kW) each

Performance

Maximum speed (http://en.wikipedia.org/wiki/V_speeds#Vno): 139 kn (160 mph, 257 km/h)
Range (http://en.wikipedia.org/wiki/Range_%28aircraft%29): 800 nmi (920 mi, 1,481 km)
Rate of climb (http://en.wikipedia.org/wiki/Rate_of_climb): 1,000 ft/min (305 m/min)

Methink the G44-A powered by the P&W monsters will take off vertically :)

This is also other figures here (specs)

http://www.fleetairarmarchive.net/Aircraft/Widgeon.html

Two Pratt & Whitney 450-hp R-985-148 engines
max speed : 290km/h (180mph)
max climb : 1,550ft/min (472m/min)
ceiling : 18,000ft (5,486m)
range : 1,600km (994miles)