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Guest GeoffC

Ground handling realism

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Guest GeoffC

Recently in the alt.games.microsoft.flight-sim newsgroups the subject of braking came up. It was suggested that a good pilot could land without brakes and get to the taxiway without using them. I believe that this is certainly against certain airlines procedures which says the autobrake must be set, however that is a secondary point really.Out of idle curiosity I decided to try it and see what would happen. To facilitate this I took my PMDG 737-700NG to EGCC on runway 24R in zero wind conditions. Just for the record this runway is 3048m long, so it's a reasonable international airport that's more than suitable for the 737. I loaded 40% fuel in both wing tanks which resulted in around 2500LB of fuel when I landed.I then did a circuit and re-established myself for a full hands off autoland which the PMDG does so well to make things easy to re-create and remove any error that I might introduce. I set myself up in the approach at 135kts, flaps 30 and speedbrake armed. As ever the autoland was perfect, right up until the point where I rolled across the 6L marker at the other end of the runway still doing 50kts. I didn't use any reverse thrust for this test. So firstly it looks like I need to continue to use the brakes as I always have, which isn't a problem as I can change the brakes as often as required for negligable cost. The other point and really the purpose of the question is to do with the ground modelling. In the newsgroup it was suggested that my result could just be poor modelling by Microsoft which is always possible. However PMDG have re-engineered many of these things as far as I understand things. Therefore was my test result a reasonable reflection of how a real 737-700 would roll or not?ThanksGeoff

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Guest EISN_CONTROL

"I didn't use any reverse thrust for this test"Reverse thrust and braking are two completely different means of decceleration, they're usually just used together.There was a thread concerning this topic recently enough and in this very forum if I remember correctly.My point is that you were testing whether an aircraft could land and exit the runway safely without the use of brakes and not without the use of any decceleration method...John http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewer

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At best it is all guess work for us non pilots (well maybe even real ones too!) since I doubt they ever go without some use of braking etc. I tried to picture this logically and at best can only think in terms of what a car would do going down a highway at 140 MPH and how long it would take to slow without any driver assisted help. Of course weight and wind (head or tail) comes to mind but whether that means it would be easier or harder to slow is another question ;-). Objects in motion tend to stay in motion, well in space anyways lol.... Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Guest GeoffC

John I am fully aware of what the reverse thrust is and only included the statement to avoid somebody submitting a reply asking that question as happened in the newsgroup. On that occassion the person also failed to answer the question in any way. For the record I was actually asking how the PMDG 737 ground handling and slow down compared with the real thing.RegardsGeoff

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First, all Aborted takeoffs and landing distances are arrived at without considering the use of Reverse Thrust. Only Braking and Speed Brakes are considered.Reverse Thrust is most effective at high speeds and should be canceled as appropriate at lower speeds , 60 knots, to avoid FOD ingestion. Also use a lot of Reverse Thrust at first, don't just crack them open to idle reverse. Boeing recommends the use of Autobrakes if installed, otherwise use common sense, if its a long runway and plenty of distance to the taxi exit stay off the brakes until about 80 to 100 knots to reduce brake wear and heat build. Brakes will last much longer and your airline and mechanics will like it too.MSFS's braking simulation could stand some realism tweaking though.Floyd

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Guest Ray51

I landed in a 737-700, SWA, at Midway. We were fully loaded and the pilot used ALOT of brake. You could feel he was really on the binders to get us stopped. We turned off with about 1000 ft left on RWY 22L which is a 6,446 ft RWY. We did not land long either.I got a very good look at the cockpit and the PMDG panel is right on. The 800/900 upgrade that changes the warning light colors is exactly correct, for SWA anyway. Was very interesting to see and understand the switch settings.Ray51Premier Airways Pilot

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Guest Buck Bolduc

You may want to let some air out of the tires. Half flat tires should slow you down a bit.He,HeDoubt any Airline would go along wit it.Regards

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Guest cactuscap

Geoff,The modeling with F2004 is more accurate than previous versions and this is most evident during taxi

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Guest GeoffC

Sean,Thanks for the reply and clarification. I guess I can take it from your answer that you can in fact land a commercial jet and get off the runway without using the brakes. Also you have confirmed my suspicion about the PMDG being very close to the real thing.

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Guest Erups

>Thanks for the reply and clarification. I guess I can take it>from your answer that you can in fact land a commercial jet>and get off the runway without using the brakes. If you have high speed taxiways (the ones at an higher then 90

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