stuck on grass

[jackmckay]

..taxing on narrow taxiway, slipping out a little bit and pow.. damn plane wheel drops like in living sand.. full afterburner, tons of force generated but somehow ground stuck...? That is most damn stupid thing in DCS, agree? Some planes are intended to land on dirt, especially soviet?

Edited November 30, 2017 by BIGNEWY
make title more descriptive

[probad]

you want to tell me how you expect 50000lbs of metal and fuel to do something besides sink into the dirt?

 

now try a flanker with no weapons and 15% fuel

taxies around on the dirt just fine

 

physics is not stupid

Edited November 29, 2017 by probad

[cichlidfan]

Some planes are intended to land on dirt, especially soviet?

 

Yes, some are, but not the one you were driving, apparently.

[jackmckay]

ground around taxiways is hardened, right? its construction standard..never soft meadow. even if it is meadow some planes still can land on it. nobody dig cliffs around taxiway man. I've lost so many hours on this "feature" that has nothing to do with RL. ... im flying mig15, mig 21 etc. but its the same with every module. and what about afterburner power? ain't that a breeze?

Edited November 29, 2017 by jackmckay

[pocketedition]

physics is not stupid

 

 

Yes they are. The idea that you can tell people whats going to happen

in their future is silly!

Edited November 29, 2017 by pocketedition
grammer

[MiG21bisFishbedL]

 

Yes they are. The idea that you can tell people whats going to happen

in the future is silly!

 

[jackmckay]

https://en.wikipedia.org/wiki/Bearing_capacity

https://en.wikipedia.org/wiki/Soil_mechanics

http://www.pta.asn.au/documents/SOILS-Proficiency-Testing-CBR.pdf

https://en.wikipedia.org/wiki/California_bearing_ratio

[cichlidfan]

ground around taxiways is hardened, right?

 

Why? Pilots are expected to keep the aircraft on the taxiway. If it were compacted enough to support significant weight then grass certainly would not grow.

 

Btw, those are nice links but they tell you nothing about test results for the ground around the taxiway.

Edited November 29, 2017 by cichlidfan

[jackmckay]

..because construction workers rolled around it with heavy rollers. http://media.wirtgen-group.com/media/04_hamm/news_and_press_releases_3/2009_plus_factor/Plus_factor_01.jpg

 

Then why T90, Abrams, BMP, or even Humvee don't slip into living sand of taxiways?

 

Its stupid, period.

[David OC]

[cichlidfan]

 

Then why T90, Abrams, BMP, or even Humvee don't slip into living sand of taxiways?

 

 

A BMP or Humvee doesn't weigh anything close to what a jet fighter weighs. In the case of something like the Abrams, please consider how many square feet of contact you have between the treads and the ground compared to the tires on an aircraft.

 

The concept is called weight distribution. Do the math. Math is your friend.

[jackmckay]

One thing is heavy impact of fast lander on runway surface another is 5km/h taxing around airbase. Its not farmland with crops. That would I understand but this is way out of course.

[pocketedition]

Little wonder he ran onto the grass, some fool parked a tractor on the taxiway.

[jackmckay]

Soil has penetration pressure value. N/cm2.. or whatever you 'muricans use there to have reference. There is certain chart for every wheel with load on it. Soil is too soft around taxiways. No doubt. .. BMP weights more than fully loaded Mig21!

[cichlidfan]

One thing is heavy impact of fast lander on runway surface another is 5km/h taxing around airbase. Its not farmland with crops. That would I understand but this is way out of course.

 

The plane weighs somewhere around 20-25 tons, standing still, on a small number of tires with very little contact with the ground. Again, do the math. Of course, landing force compounds the problem, which is why the runway is paved with a very large gravel bed under the pavement.

[jackmckay]

Here: http://www.boeing.com/assets/pdf/commercial/airports/faqs/calctirecontactarea.pdf

http://www.dtic.mil/dtic/tr/fulltext/u2/a279100.pdf

[cichlidfan]

Here: http://www.boeing.com/assets/pdf/commercial/airports/faqs/calctirecontactarea.pdf

http://www.dtic.mil/dtic/tr/fulltext/u2/a279100.pdf

 

Again, very nice links but they do not answer the pertinent question of what the test values for the ground next a runway are.

 

Edit. I also would not assume that ED models the weight of the various ground units like they do the aircraft since it is not overly relevant whereas the weight of the aircraft is very relevant.

Edited November 29, 2017 by cichlidfan

[jackmckay]

 

Let the ED team answers that question?

[jackmckay]

[cichlidfan]

 

Let the ED team answers that question?

 

I take it that you are assuming that the aircraft is not stuck. How do you know? Momentum could have gotten it that far.

[jackmckay]

https://esdac.jrc.ec.europa.eu/images/Eudasm/GE/PDF/soil_map_of_georgia.pdf

[jackmckay]

I take it that you are assuming that the aircraft is not stuck. How do you know? Momentum could have gotten it that far.

 

Take Mig15 with 50% of fuel and hit the taxiway. Slip. No way that it can stuck in that soil easy. Plane has shock absorbers, wheels have inflated tires. No peak rigid pressure impulse here only very soft and gradual pressure distribution on tire face. And plane always has this inertial pulsation of some kind there.

Edited November 30, 2017 by jackmckay

[mkiii]

I can certainly attest that a lightly loaded combat aircraft (Tornado in my experience) will quite happily bog itself in up to the axles if it leaves the taxyway, even with just one oleo. Why would anyone think otherwise?

 

Old Soviet aircraft may be designed to cope with rough strips, but not turf laid over soil. Even something as light as a DH Chipmunk, operating from a (rolled) grass strip, has bogged in (and nosed over) in my experience when it deviated from the prepared grass area.

[Destroyer37]

 

And on this day, a corporate pilot lost his dream job.

[quarz]

${1}

 

Edited November 30, 2017 by quarz