New FSAviator Martin M-130 Clipper FD

[Randy_Cain]

Hi,

Tom, Colin is onto something! This doesn't eliminate the AFCAD issues, but CoG is the problem everywhere else!

Here's the original from the 2007 release:

station_load.0 = 360, 18,0,-5, Pilots (2)
station_load.1 = 540, 12,0,-5, Other crew (3)
station_load.2 = 2040, -8,0,-9, 12 pax (46 max)
station_load.3 = 510, -7,0, -9, Freight and mail

Jens made one mistake here (I assume from working with the Shorts for so long where cargo and mail was stored in back) ..the cargo and bags in an M-130 were stored in the bow, under the pilot and copilot...not in the rear of the plane. The only thing back there was the stairs to the main passenger entrance/exit. Behind that was only a door to the tail to access all the control cables. ..empty space.

I always compensated for this by taking that 510 pounds out of station.3, leaving it at 0. I notice that in the new aircraft.cfg, ALL passengers and cargo are at 0,0,0. On land, this may not make a difference, but in WATER, I contend that it does. This would explain much. It's an "empty see-saw" with all the weight on the fulcrum.

I didn't realize this til I started reading the rest of the .cfg file a few minutes ago.

As to the 2D issue, if we can't incorporate Doug's gauge, or if it doesn't work here, can we at least get a 1024x768 sheet of 0,0,0 (main.bmp) black so we don't load to a black screen? (..cockpit view)

On the PHNL issue (as well as any other AFCADs built to handle flying boat or amphibian AI), what do you think might work? Do we need a Flatten file for the water surface and taxi area? Would an exclusion file help eliminate the bottom scrapes? I do seem to be having real problems with this plane finding "0" feet wide concrete apron routes and runways that lead to either an overstress or crash....even at 10 knots.

Yours,


P.S. I just tried the old station load defaults on the new version, but it didn't work, so I took it back out. The plane still looses pitch stability and flips backwards at as little as 10 knots..especially when trying to turn it around on 2 engines. I was using open water, miles from land, but near Oahu. I tried realweather and "Fair Weather" with surface winds at 0 knots, then again at 10 knots (realweather) No Active Sky this time.

[Col7777]

Randy,

You might not want to do this but keep the contact points & light sections then change the rest of the cfg for the contents of a similar aircraft just to see if it works better, not forgeteing the air file as well.
I sometimes have to do this if I change a flyable to an ai version.

[Randy_Cain]

Hi,

Colin, I sent you a PM.

Tom, I noticed that in the Weight and Balance section, the CoG has been moved from "empty_weight_CG_position = -1, 0, -3" to "empty_weight_CG_position = 0, 0, 0". Could this be having an impact on it's stability and how much water the plane is displacing? If so, that could explain ground scrapes I didn't experience before.

I noticed the other entries in this section have been significantly increased as well. Other entries in this section have been at least doubled. I would think that would have made the boat more stable, not less...as demonstrated in the change in flight handling.

Oh, I noticed that Jen's original numbers on those last 4 contact points (900-1000) were the same in his as they are in yours. Maybe this change was just in hopes of an improvement.

I would just like to be able to use this plane in conjunction with airports that have AI amphib and flying boat traffic and scenery, and to "park" the plane, as opposed to just taking off immediately, then landing and shutting down. (..although I do realize that really was what actually happened, but we don't have tug boats )

Yours,

[Tom/CalClassic]

Hi,

Try these things - these are NOT the final numbers, just things to try:

1. Move the "main gear" points back 5 feet to avoid tipping backward:

[contact_points]
static_pitch = 2
static_cg_height = 13.0

point.0 = 4, -10, -16.1, -13.5, 3500, 0, 0, 0, 0.55, 5.2, 0.4, 0, 0, 2, 0, 0
point.1 = 4, -10 16.1, -13.5, 3500, 0, 0, 0, 0.55, 5.2, 0.4, 0, 0, 3, 0, 0
point.2 = 4, 25.578, 0, -14.002, 3500, 0, 0, 20, 0.2, 6.5, 0.6, 0, 0, 0, 0, 0
point.3 = 2, 0, -65, 1.5, 900, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0
point.4 = 2, 0, 65, 1.5, 900, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0
point.5 = 2, -61.113, 0, -2.9, 900, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 0
point.6 = 2, 30.65, 0, -10.005, 1000, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0

Note I also changed the static_cg_height number.

2. Increase the Pitch MOI to avoid tipping back and forth.

empty_weight_pitch_MOI = 3300000


I increased it by a factor or 10, but this should be reduced just until you don't have this problem anymore. This number is probably way too high.

A flatten would probably help at PHNL; I'll look into making a new version that is seaplane compatible.

Hope this helps,

[Tom/CalClassic]

Hi,

A reply from FSAviator:

The Martin M-130 VC has always been a well designed above average example. It has elevator and rudder trim wheels with tooltips to allow pre flight adjustment. Virtual cockpits do not need trim gauges.

I see no reason why the proposed 'omit CV' gauge should not work in the Martin and it seems to be an ideal solution. However I have not had time to test it. Regarding the 'black screen' I intended a 'clear view'. To obtain clear view open each panel.cfg and find


// VC pop up windows

[Window Titles]
Window00=nil
Window01=Radios
Window02=GPS
Window03=Engineers panel

then just remove the line

Window00=nil


<<I notice that in the new aircraft.cfg, ALL passengers and cargo are at 0,0,0. On land, this may not make a difference, but in WATER, I contend that it does. This would explain much. It's an "empty see-saw" with all the weight on the fulcrum. >>

Causing the boat to exhibit wave motion (behaving like a see saw on the water) was intentional. However I made an exaggerated bouncing motion worse and it can throw the aircraft clear of the water at low speed. All of that bouncing effect is encoded in the contact points. It is not a payload issue. It has some relevance to current immersion which depends on current IAS (headwind vector) but the error is entirely a contact point error. Hydroplane contact points are a pain to get right.

Payload placement isn't relevant to the problem or solution, but the way I encode payload and fuel is queried from time to time so it is worth explaining again here.

MSFS does not calculate payload inertia. It only calculates the origin (CoG) and vector length of the weight vector. Historically the problem has always been FS consumers altering payload weight without rebalancing the aeroplane until CoG was again co-incident with CoL, but then reporting that the FD were broken when they were accurately demonstrating consumer (captaincy) loading error. I became so tired of dealing with this issue that I decided I would always release only FD in which the user can alter payload weight without needing to rebalance the aeroplane. Most MSFS users just don't cope with CoG v CoL calculation and if faced with variable CoG v CoL soon demand automated load and balance software to solve the problem for them. I see that as pointless complexity.

Tom likes to recreate that problem in some/many Calclassic propliners and I can live with that. I removed the problem from the Martin. Moving payload equidistant from CoG fore and aft without moving CoG will change nothing. Moving CoG away from CoL will unbalance the boat in flight and alter the elevator trim required for take off. If anyone varies CoG they are responsible for recalculating the trim consequence of the loading error imposed.

I have added the MOI of the payload to each base MOI value because that is how MSFS works. Moving payload in MSFS potentially alters CoG and unbalances the aircraft, but has zero impact on MOI in any axis. My code is designed to ensure that consumers can alter both crew weight and payload weight without altering CoG. Consumers are free to import CoG errors by variation of the cfg if they really have that intention, but users can no longer unbalance the Martin using the on screen menu and many will avoid errors that are very difficult to diagnose after the fact.

MSFS does attempt to calculate and vary fuel MOI, but it miscalculates. Consequently I place the correct mass of fuel, (if necessary using a false volume), always at a false location, where it will deliver a 'realistic' variable MOI consequence as it burns off. Until/unless we have multi user on line virtual cockpit simulation interfaces for the Calclassic propliners I see no point in imposing fuel trimming requirements on single user flight simulation. My code simulates the large crew of vintage and classic era propliners doing their jobs and doing the fuel trimming competently so that fuel CoG does not vary whilst fuel MOI reduces realistically as the flight progresses.

Stability and damping for each axis are encoded in the air file not the aircraft.cfg.

Coding the real world values for various things is not the way to obtain realistic flight dynamics in MSFS. It works differently to real life.

My propliner FD are never compatible with the MSFS AI engine. It cannot tolerate proliner realism which is why calclassic AI FD are based on jet aircraft.

FSAviator

[Tom/CalClassic]

I have updated the PHNL scenery with flat water and I even added a pier.



Get it from my Scenery page. If you have it installed aleady, just use the installer and that should be all you need to do.

Enjoy,

[eddiejez]

Hi
ive tried many different contact points and weight configurations but still have problems getting the plane in the air its lovley once in the air , think the problem may be in the air file its self as you say its ok on flat water but people may want to fly the routs the real aircraft flew

Rgds Edd

[Randy_Cain]

Hi,

I'm in Idaho City, just checking in. There are a couple of flying boat fans over at "The Old Hangar" forum that have reported the same thing that I have. To load the plane, fly your flight, then land and shut down in clear or fair weather is just fine...but taxiing is a problem.

Sorry, I didn't have time to check the new recommendations, Tom. I will as soon as I get back.

I gotta run. This is a public PC, so see ya'll soon. ;D

[weberjf]

I flipped over before I could even start the engines - on the water runway at Longbeach.

[Tom/CalClassic]

Hi,

FSAviator has created new Contact Points that seem to fix most of it. I can still crash if I'm not careful, but it takes care of most of it. Download the package again and copy the 2 aircraft.cfg files into the proper folders, overwriting the originals. There is one in the main zip file for the later M-130, and one in the 1935 folder for the original version.

I find that it is now more difficult to steer - use your rudder to steer at higher speeds, and differential engine thrust for slower speeds. Ah, use both!

For differential thrust, I find that if you start with all engines at about half throttle, then press E12 (or E34) and then full throttle, you will come around OK, if you use the rudder to help. Don't expect to make any tight circles, though - plan ahead. Press E1234 to get back control of all engines.

Hope this helps,

[eddiejez]

Hi Tom
ok gonna download again and try it .Randys repaints work fine in fsx

rgds Edd

[johnl]

For manoevering on the water, try keeping both inboard engines throttled back, and apply power to an outboard engine only - this is how the Short FBs did it.

[eddiejez]

Hi

the m130 seems fine now only have a problem in one place now but that could be the sceenery ? as for steering it in reality it was probably tugged into a mooring point by a boat but as you say can be turned by engine power

rgds Edd

[Deleted]

Hello all,

Flew the M-130 with FSAviator's new contact points, and it behaves very well indeed. Like others, I was having a bit of a problem with porposing at all speeds on the water, but I never had it flip over backwards on me!

Rotorpilot

[jensbk]

Aug 22, 2008 3:40:18 GMT -5 Randy_Cain said:

Hi,
Jens made one mistake here (I assume from working with the Shorts for so long where cargo and mail was stored in back) ..the cargo and bags in an M-130 were stored in the bow, under the pilot and copilot...not in the rear of the plane. The only thing back there was the stairs to the main passenger entrance/exit. Behind that was only a door to the tail to access all the control cables. ..empty space.

Randy, the M130 had room for cargo and mail in the nose, and two compartments for baggage - one in front of the cabin(s), and one in the rear, just behind the ventral airstairs. The rear baggage hold had a capacity of 1248 lbs. My source is Stan Cohen: Wings to the Orient.

I'm a bit surprised about all this discussion of the M130 FDE - obviously, FSAviators idea to recreate the original 1935 configuration with 2-pitch propellers is very interesting, but otherwise I think the FDE's included with my original release are very good (taxiing, takeoff, climb, cruise, landing...) - what are the reasons to change them?

best regards

Jens