View Full Version : Landing Gear Damage

July 12th, 2010, 10:15
Hello All,

Perhaps this isn't exactly "Flight Dynamics", but I am trying to figure out where the variable is for determining whether the landing gear has suffered damage. After an aircraft has been belly landed, retractable landing gear will no longer extend. I am trying to adjust an aircraft so that the landing gear will always work. I am guessing there is a variable I need to reset.

- Ivan.

July 12th, 2010, 16:34
After the belly landing, how are you "testing" to see if the gear extends ? Does going back to 'Free Flight' and starting the flight again, work ?

Regardless.. try looking at the failures screen.. look for any 'check marks' to see what exaclty failed.

I've never gone down this route, as I just treat a belly-landing as damage beyond flyable.. and end the flight.. lol

I've done a bit of gauge coding.. and have seen the variables. I don't recall one that's gear specific, but ther are failure keys for electrical and hydraulic systems... either of which could render the gear useless.


The logic could be an invisible gauge that tests a for a TRUE failure, and then toggles it.

July 12th, 2010, 17:16
You may need to reselect the airplane. It appears that some versions of FS may have a damage memory, ie. hard landings can accumulate to a failure under circumstances that do not warrant one. I have particularly seen this with tail wheels.

Good luck! T

Milton Shupe
July 12th, 2010, 17:53
You really have to look no further than the contact points for gear:

point.0 = 1, -19.904, 0.000, -0.637, 2200, 0, 0.3, 180, 0.51, 2.0, 0.5, 3, 5, 0, 139, 175.2
point.1 = 1, 2.890, -6.417, -5.987, 2200, 1, 0.8, 0, 1.15, 1.1, 0.5, 5, 5, 2, 139, 175.2
point.2 = 1, 2.890, 6.417, -5.987, 2200, 2, 0.8, 0, 1.15, 1.1, 0.5, 5, 5, 3, 139, 175.2

Parameter 5:
5 (3200) Impact Damage Threshold The speed at which an impact with the ground can cause damage (feet/min).

Parameter 15 and 16:
15 (0) Airspeed Limit This is the speed at which landing gear extension becomes inhibited (knots). Not used for scrape points or non-retractable gear.
16 (200) Damage from Airspeed The speed above which the landing gear accrues damage (knots). Not used for scrape points or non-retractable gear.

BTW, if you do not have it, get the Aircraft Container SDK for explanations of all these things in the aircraft.cfg.


July 12th, 2010, 18:19
Hi Milton...

Do those damage paramters apply to a gear-up, belly landing ?

Milton Shupe
July 12th, 2010, 19:36
I do not think so Brett.

July 12th, 2010, 21:09
For the belly up landing, the scrape points will govern... It is possible to damage the engines if there are scrape points for the props.


July 13th, 2010, 02:51
I think the prop scrape points, are the prop diameter..

July 13th, 2010, 11:10
I have in the past set a scrape point for the props, in the FSX DC2 this triggered a prop damage visual and also damaged the engines. I haven't experimented to see whether or not just the prop diameter will cause these effects. Easy enough to try.... make a really big prop diameter.

Cheers: T

July 14th, 2010, 19:15

Actually what I am trying to do is to build a true amphibian for CFS1 such as a PBY-5A. I can build a flight model that allows for landing on its scrape points and then taking off again. The problem is that once it has done that, the landing gear doesn't work any more.

I test by taking off from an airfield, landing somewhere on water (or land, because once the class is changed, it doesn't matter) and then taking off again to land at an airfield. The landing gear won't extend for the second landing.

- Ivan.

Milton Shupe
July 18th, 2010, 10:47
Ivan, does CFS1 not have float points? That is what you should be using.

In air file table 1004, type gear=4, and you can set steering there as well if you have water rudders.

July 19th, 2010, 13:02
Hi Milton Shupe,

Obviously building a land plane is easy. We all do that. Building a flying boat flight model isn't really all that hard either. I found that having the scrape points near even with the level of the CoG allows the plane to slide pretty well. Another method I have used to get the flying boat off the water is to adjust the ground effect graph to increase lift at VERY low altitudes to simulate a planing hull raising the aircraft off the water. Once that happens, friction is reduced and the plane takes off easily. Either method works reasonably without seriously screwing up the performance in other areas.

The problem is that with something like the PBY-5, you have both a hull for landing in water and wheels for runways. I am trying to build a plane that will do both. In this case, a water landing is basically a belly landing. I have no issues with a water landing and a subsequent take-off, but the problem is that after a belly landing, the landing gear won't extend again....

- Ivan.

July 19th, 2010, 17:53
Is it possible that you need to do something with the damage profile if this is from the CFS series?

Cheers: T

July 20th, 2010, 12:06
Hi Fliger747,

I am pretty sure that the DP file doesn't affect this. I believe it is one of those internal variables such as the ones that determine whether the landing gear is up or down or whether the wings have fallen off yet or what the current WEP time count is.

I figure that if I can find out what this variable is, I can have the MDL file reset it to always work.

- Ivan.

July 20th, 2010, 17:27

Some wierd things go on in the bowls of the fs/cfs series. Even in FSX it is necessary to start an amphib out on dry land! However you can land on water, lower the gear and taxi onto shore, taxi back into the water, raise the gear and takeoff on water.....

Cheers: T