I was watching a show last week on the crash of American 1420. The MD-80 crashed in Little Rock in 1999 while landing in a severe thunderstorm (heavy rain, hail, crosswinds of 45knts, gusts to 70knts). The crew made a terrible mistake by trying to land. The plane skidded down the runway, overshot it and hit a wall. 10 dead including pilot.Key factor to the overshoot was failure of the crew to set the spoilers to deploy on landing.I have to admit that I have landed in FS a number of times where for whatever reason the spoilers do not deploy....of cours in the sim the plane still stops.My question is, do the ground spoilers have any effect at all in the sim ?Mark.

yup. try two takeoff's one with, one without. check the performance of the a/c. tt

Hi Mark,Automatic spoiler deployment isn't really neccessary. If they do not deploy automatically, you just have to extend them manually.Some planes tend to skip back into the air if the spoilers don't extend upon touchdown.The main difference is, that the spoilers in any FS aren't really comparable with real spoilers.In FS9, the simulated spoilers are, naturaly, flight spoilers or speedbrakes.Groundspoilers, which extend on the ground, either extend to a much further angle or more or all spoiler panels deploy.In any case they destroy much more lift than the flight spoilers.The point is, you need to extend the groundspoilers in real life to get the weight onto the wheels for better braking action, in FS the simulated flightspoilers aren't very effective on ground.RegardsBernt Stolle Capt 767

Mark,I watched the same program last week (National Geographic, right?)...I thought it was very well done and provided a good luck at the whole picture surrounding that incident.Anyway, what you have to remember is that the conditions were absolutely horrible when they were landing. As the TV said, it was not even legal for them to be landing, not only due to visibility but also due to the crosswind. Also, the runway was soaking wet (I beleive they were sliding for awhile) and I sincerely doubt that he got it down right near the beginning of the rwy. All of this factored in, that plane was impossible to stop on the runway without the spoilers. However, if it had occured on a day where the wind was blowing straight down the runway at them and the pavement was completely dry, they probably would have been able to stop with brakes and reverse thrust (at least they wouldn't have made it as far into that metal tower). FS2004, unfortuantely, doesn't model the condition of the runway from rain or snow. So, the braking action in FS is always perfect. That's why the spoilers aren't such a huge deal, especially when you have a large runway to play with...Anyway, those are my thoughts...-Marc

In the aircraft_geometry section of aircraft.cfg I noticed this statement:spoiler_limit = 45.000which I assume is the positive deflection if set up for all or nothing with the assigned toggle key. While FS only provides one spoiler set, and you increase the angle stated above, I would suspect this would increase the spoiler effect. I do not know if this has any effect on the vissual model.I have also seen a statemenr regarding spoiler_increment somewhere nor have I digested the docs in the aircraft container SDK or panel SDK. So as few simple questions:1. In real world aircraft, are flight and ground spoilers the same wing elements but according to imminent function just using a greater deflection, or are they seperately controled surfaces?2. Can one key (or axis control) be assigned to increment a spoiler to act as a flight spoiler and another via ground spoiler arming to force or allow on ground contact a spoiler to be fully deployed as a ground spoiler?

>1. In real world aircraft, are flight and ground spoilers the>same wing elements but according to imminent function just>using a greater deflection, or are they seperately controled>surfaces?>Flight and ground spoilers can be different wing elements, that is, on some airplanes the ground spoilers are a spoiler panels that only deploy on the ground. Where the same spoiler panels are used both in flight and on the ground, the deflection angle can be different.Don S.

Just some interesting info from an MD-80 series pilot (me!)The spoilers affect braking ability significantly on the 80 series aircraft. The autobrakes are tied to the spoiler deployment which senses weight on wheels and looks at throttle position. If the spoilers do not deploy you have approximately 60% less braking effectiveness until you get full weight on wheels after the nose comes down and you have slowed a good bit. Spoiler deployment and problems with it have contributed to several accidents and incidents with this aircraft in the last few years. We (Delta) had one go off the runway in KPNS about three months back due to a spoiler/brake problem. Some aircraft it does not matter a whole lot, but with this aircraft it is critical to getting stoped in the shortest distance. Hornit

Hi Hornit,You are lucky guys. When did delta add autobrakes to their md80s???Ours still don't have them and these stone age birds are beeing phased out within this year.We have a lot of pilots that transition now from the md80 to the 767 and they are amazed how advanced the 767 is. Unbelievable!RegardsBernt Stolle Capt 767

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hornit, how would you compare the performance and flight characteristics to something as a b737/57/or even 67? Im jus curious, but i would like to see a comparison of a aircraft with jets on the back of it and with the wings placed a little further back that a plane such as a 67 with wing a little bit further foward and the jets under the wing...And for the show most of us saw, with the current conditions at that time, wind shear, vis at 1700ft, winds at 40kts, gusting to 60 or so kts, im shure that was all the ingrediants needed to make a approach with one mistake being made, into a total disaster. If i was the flight captain, i would of decided to divert to a better field. I am 14 and working on my PPL and my dream is to go commercial flying 757-300's for coa, but i think if i wasnt able to see the field, (notice how the co-pilot had to point it out several times) i would of definentaly diverted. The over all conditions were TERRIBLE

>In the aircraft_geometry section of aircraft.cfg I noticed>this statement:>>spoiler_limit = 45.000>>which I assume is the positive deflection if set up for all or>nothing with the assigned toggle key. While FS only provides>one spoiler set, and you increase the angle stated above, I>would suspect this would increase the spoiler effect. I do not>know if this has any effect on the vissual model.>Guys, this is interesting, did anybody try to increase it?

Regarding the MD-80:Each wing has two flight spoilers, which are operative during all phases of the flight, and one ground spoiler, which only deploys on the ground. In 1999, an American A300 landed at JFK, but the aircraft bounced on touchdown. Unfortunately, the spoilers went into "ground mode" after the first touchdown, making the A300 descend rapidly onto the runway. The final touchdown was in excess of 3G, but the aircraft returned to service after an inspection.Regarding the AA incident in June 1999: The crew were allegedly quite tired, and this could have impaired their judgement. The position of the wings/engines made no difference in this incident.From airdisaster.com:Winds at Little Rock, Arkansas were reported from 190

Not an FDE guru, but it appears from the .air file that the basic spoiler action is determined by a drag factor * spoiler angle and a lift factor * spoiler angle. There is also the capability to define spoileron action. Spoiler angle limit, spoiler cycle time, and spoiler auto deploy are also given. So spoiler action appears to be linear, not accounting for separate ground spoiler surfaces.scott s..

>Not an FDE guru, but it appears from the .air file that the>basic spoiler action is determined by a drag factor * spoiler>angle and a lift factor * spoiler angle. There is also the>capability to define spoileron action. Spoiler angle limit,>spoiler cycle time, and spoiler auto deploy are also given. >So spoiler action appears to be linear, not accounting for>separate ground spoiler surfaces.>>scott s.>.>Hello Scott,Thanks for the info, sorry being dumb, but is there a way to increase efficiency of the spoiler? I guess the angle of 45 degrees (see in the above) should be increased, for example to 65? Does it sound right to you? If you have an idea how to increase spoiler efficiency (particularly on landing) could you please post it here.Thanks,Dirk.

I did on the I think was the POSKY CRJ-200 which while maybe true to the actual prototype was not as effective as I hoped and it did seem to take effect. The POSKY also tended to float even with the spoiler deployed on the ground and this helped.Now it was stated somewhere that changes to the aircraft.cfg file would not take effect until the .air file was recompiled with AirEdit or I guess FSEdit, but that has not been my experience.I should note that POSKY has available updated .air files for this model. As noted on their forums, the real CRJ is slippery and does not like to quit flying.It should also be noted that inboard spoiler/speed brakes are more effective only at lower speeds because in most cases at higher speeds the airflow tends to concentrate closer to the wing tips and outboard controls become more effective with inboard control surfaces becoming less effective.