As announced in another thread - I will post regularly the goodies of XP12: here the difference of braking on a dry and an icy runway. Accelerating in both conditions to around 65 kn, then throttle zero and brakes full.

Dry

Icy:

 

As no further discussion on this topic came up: "some people" ^TM 😁 seem to be so shocked and awed that they didn't find a counter argument 😅.

More stuff to follow ...

Edited September 16, 20223 yr by flying_carpet

Thx for sharing @flying_carpet !

1 hour ago, jcomm said:

Thx for sharing @flying_carpet !

You're welcome. BTW, already XP 9 (14 years ago) or even earlier had icy runways - not visually but ...

Nice show. I know it's a challenge to do in simulation because we can't even get it right in real world aviation. You can easily test wet conditions and the performance charts I use are based on actual wet conditions. When you get into snow, ice and slush, testing gets difficult. It's just hard to test those conditions because the braking response changes at different temperatures. In that case, you apply a factor. In fact, some manufacturers will apply a factor for wet runways. In the Airforce, we used RSC, which was for depth in tenths of an inch. We used RCR, which was a runway condition reading. They would drag a device out on the runways/taxiways and brake it. It would come back with a reading and they would report it from 0 to 23. 23 was dry, 12 was wet and 6 was icy. You would run that through a correction grid or your FMS would apply it. The RSC would significantly degrade your capability. In the civil world, you follow the manufacturer's recommendation and use their specified factor. There is also a factor specified by the FAA based on your type of operation, but they mostly defer to the manufacturer. 

Even the different governing bodies look at this differently. For example, if I operate an aircraft that is certified by the FAA, I operate normally if the runway is wet and account for the accel stop distance. In that case, I am at 35ft at the end of accel go. If I operate an aircraft that is certified by EASA or JAA, a wet runway is considered contaminated. Not only do I need to account for the additional stop distance, I have to account for the additional distance needed to get to 35ft. The FAA handles contaminated runways loosely, but the other governing bodies chose a standard and certify by it. 

I know this is a bunch of useless information, but thought it was worth the insight. I am glad that this is being considered as it generates realism. Wet/contaminated runways was always on my mind when I flew heavies, along with climb gradients/obstacles. Its awesome when a sim forces you to consider these things and make you pay for it if you don't.

Rick

 

13 hours ago, G550flyer said:

<snip>

Its awesome when a sim forces you to consider these things and make you pay for it if you don't.

👍

And X-Plane does a lot of "forces you to consider these things and make you pay for it if you don't." More similar videos to be expected 😉

There's no doubt that XP has always had the edge over other sims for flight modeling.  Nothing is perfect and occasionally other sims have done better in certain flight envelopes but this is solid evidence that flight model is the most important in XP12 - and great job on the videos too