Donstim

Yes, you should gradually bleed off the wind correction during the final approach to be at Vref at the 50 foot height over the threshold in order to achieve the certified landing distance.Don S.

From the standpoint of how the airplanes are certified for landing distance, the "correct" procedure would be to cross the threshold at Vref and conduct a normal flare and thrust reduction (thrust levers to idle around 50 feet, rotate to about 5 degree nose up pitch at around 30 feet). This will bleed off additional speed, putting you below Vref at touchdown.Some operators' procedures may differ from this. For example, one major operator says to maintain the gust additive (up to a maximum of 20 knots) at the threshold, then conduct a normal flare.Don S.

If you are doing a manual landing, you should bleed off the speed additive so that you are at Vref at the threshold (at a height of 50 feet above it). Landing distances are based on being at Vref at the threshold.Don S.

Would be nice to have the new Vertical Situation Display now available on the NG's as well. Big improvement for vertical flight path awareness similar to what the map display does for the lateral path.Don S.

Hi Martin,Thanks for your reply and suggestion. I have since seen that many others have had the same problems with the latest versions of ZoneAlarm and SBRelay. Temporarily, I think I will just use the Microsoft XP firewall while flying online. That will give me some time to look into switching over to Kerio or, alternatively, maybe Zone Labs can fix the issue with ZoneAlarm.In the meantime, I suggest that everyone reading this help to spread the word that the current version of ZoneAlarm is incompatible with SBRelay.Don S.

>Personally, I can't understand why one would need additional>training to move to the modern PFD display. All these pilots>have flown several planes and are used to different cockpits. All pilots? How do you know you this?>I understand if the switch is from Boeing to Airbus, but it's>just a couple displays. Just a couple displays? These displays provide the primary information for heads down flight. It is imperative that pilots be fully competent with them. When things go wrong, the display had better be second nature to the pilot.If a pilot can't switch between the>the two styles, then I wonder what it says about their>ability. I assume it's an FAA thing, in which case we all>know the government regulates our lives beyond>ridiculousness.And what if it's an operator philosophy thing? Does that make it alright? Some operators do switch back and forth between different display formats, but not Southwest. I'm sorry that you feel the FAA is somehow regulating your life beyond ridiculousness. It is the flying public that demands the current extremely high level of safety (especially compared to other modes of transportation) that we have in today's commercial air transportation.Don S.

I use NAV 2004 and don't notice any pauses occurring in FS. Sometimes I use FS Autostart to shut things down, but even then I don't really notice any signficant performance difference.Don S.

Have you tried it with your firewall turned off? I have the same problem, but I'm using ZoneAlarm for my firewall. If I completely shut down ZoneAlarm, the FSRelay session immediately pops up in the MSFS multiplayer session search box.Since I don't want to be online for that long without the firewall, I've been using the "host" session option rather than "join" session. It then connects to the FS2002 FSRelay server and seems to work okay. At least, I haven't gotten any complaints from online ATC. I hope that's okay as a temporary workaround.Don S.

I am unable to find the SBRelay multiplayer session in FS2004 with ZoneAlarm 5.1.011.000 active. If I shut down ZoneAlarm, the session pops up in the FS multiplayer search box. I have given SBRelay, FS, DirectPlay Server, DirectPlay Helper, and Squawkbox server rights in ZoneAlarm. Even with program control turned off in ZoneAlarm, the SBRelay does not come up in the Join Multiplayer Session search box.I did not have this problem with earlier versions of ZoneAlarm (and prior to WinXP SP2).Don S.

> While the PLI is not there, the AOAindication on the>PFD option IS, certainly we are not missing the>function that the PLI gives.>Hi Randy,Actually, the AOA indicator does not provide equivalent functionality to the PLI indication. The PLI indication shows the pitch attitude corresponding to stick shaker activation, while the AOA indicator shows the angle-of-attack for stick shaker activation. Also, the PLI is on the primary flight display that the pilot will be using as the primary instrument for flight control during heads-down flight.Don S.

Randy,I really doubt if runway condition (wet, dry, or snow-covered) makes a difference in FS 2004 (or even runway slope for that matter), but flap position and altitude sure do.Best regards,Don S.

Yes, so many variables and insufficient data to answer the question. The PMDG documentation does not indicate what flap setting or altitude it corresponds to, which makes it nearly worthless except as a general guide.Don S.

Hi Paul,Interesting results. Note that the 150.1 lb weight in the takeoff performance document is a climb limit weight, and is independent of runway length. It does not matter whether the runway is 6000 feet long, or 12,000 feet long.The climb limit weight for an airplane depends on thrust, flap configuration, speed, and OAT. The PMDG documentation only provides info on two of these variables -- OAT and speed (V2 speed). We do not know what thrust level or flap configuration the 150.1 lb weight corresponds to. (This make the performance data provided by PMDG pretty worthless.) It very well could be that the data are for flaps 5, which would have better climb performance than flaps 15. You are probably above the climb limit weight for flaps 15, which explains why you cannot even maintain level flight. It could also be that the thrust level is for full rated thrust with the air conditioning bleeds turned off. By not taking bleed air off the engines, more takeoff thrust is provded (if PMDG models this effect).Another aspect is that PMDG may have decided that matching the climb performance at weights above the maximim limitation weight was unnecessary since you should not be operating there anyway.If you want to do any more testing, may I suggest you try your takeoff at 50 degrees C OAT at the climb performance limit weight of 123,000 lb? This is within the limitations weight. You can try different flap settings (lower is better) and turning the air conditioning bleeds off to get better climb performance. With an engine cut at V1, you should just barely be able to climb away (about 316 feet/minute climb rate at a V2 of 130 knots, for example). This is not a runway limit test, so feel free to use a longer runway.For a runway limit test, you will need to find a runway where the runway limit weight is lower than the climb limit weight. For example, at 50 degrees C, you can use a 5000 foot runway, which has a limit weight of 121,300 lb. The runway limit weight also depends on the flap setting and the thrust level, with higher flap settings providing better performance.Best of luck,Don S.

Those yellow "wings" are called the pitch limit indication, and are also referred to as "whiskers." On more recently produced airplanes, they will also appear with flaps up as you get closer to the stick shaker angle of attack. (I don't remember off the top of my head what the triggering angle is.)Don S.

Robert --I would be interesting to know which part of my explanation you found misleading. Like you, I pointed out that a given operator's maximum weights may be less than the maximum certificated weight of the airplane. I also pointed out that all of the weight requirements must be met for every takeoff -- whether it be the structural limitation weight, the takeoff runway limit weight, or the climb limit weight.Where we appear to differ, and where I find your response to be misleading, is that you seem to imply that the structural limit weight has something to do with airplane performance. It does not. And as I and others have shown, you may see those runway end lights (and whatever is beyond) up close and personal in the PMDG 737NG even when operating within all of the weight limitations if you have an engine failure near V1 speed.I don't really find that to reduce the enjoyment I get in any way from your team's excellent simulation, though. I don't know if it is even possible nor worth the time and effort to try to match the actual airplane's performance capability that accurately in a pretty darn inexpensive product built on a pretty darn inexpensive piece of flight simulation software.One other thing I recently noticed that maybe you could clear up. Although your limitations documentation notes the maximum weights of the -600, -700, -800, -900 to be 127,000 lb, 133,500 lb, 174, 200 lb, and 174,200 lb, respectively, the config files have the maximum weights set at 144,000, 153,500, 173,000, and 174,500 lb, respectively. Why are these different?Thanks,Don S.

Hi Floyd,I've essentially repeated your results. The top of the red checkerboard on the airspeed tape display actually notes where stall warning (stick shaker) will occur. The stall speed should be at least 3 knots or 3% lower than that speed. (However, I don't know if MSFS 2004 allows a distinction between stall warning and stall -- they may occur at the same speed in the game.)I found that stall warning occurred 10-20 knots above the top of the red checkerboard in every flap configuration on the -700 except flaps up. With flaps up, the stall warning appeared to occur at about the right speed. I didn't check any of the other airplane models (nor did I check to make sure that the speed tape display is correct).I noticed that attempting after taking off with an engine failure at KSNA under the conditions you used, I was unable to climb at the V2 speed.I tried Bernardo's scenario in the -800 and did not have any problems. The airplane climbed (albeit very slowly) at V2, the flight director command bars commanded to V2, and it stayed in TO/GA mode.I guess the moral of the story is that to be safe we'd better consider adding a few knots to the published speeds and stay well away from the top of the red checkerboard!Don S.

If the engine fails before you get to V2 speed, the flight director bars will command to V2. If you are between V2 and V2 + 20 when the engine fails, the flight director bars will command to your current speed. And if you are above V2 + 20, the flight director bars will command to V2 + 20.Don S.

Hi Paul,Let me give it a try. The maximum weights shown in the limitations section are the maximum weights that the airplane can be operated at regardless of the runway or environmental conditions. These weights are normally considered the structural limit weights, though often simply reflect the maximum weight capability that the airline has purchased.I don't know where PMDG got their maximum weight limitations from. The maximum takeoff weight limit that has been certified for the 737-600 is 143,500. (You can find this information here: http://www.airweb.faa.gov/Regulatory_and_G...FILE/A16WE.pdf) As I said, though, different airlines may purchase different maximum weight capabilities (but not more than the maximum that has been certified). PMDG may have gotten their information from an airline that purchased a lower weight capability.In addition to the maximum weight that can ever be used, there are performance requirements that can affect the maximum weight that can be used for any takeoff. One of these is based on runway length, another is based on the climbout after takeoff. There are others, but these are the only two that we can hope to address with the PMDG documentation. The maximum weight that can be taken off from a specific runway length is provided in the PMDG takeoff data tables, as is the maximum weight that meets the climb requirements (the numbers is yellow).Now, you must meet all of these requirements for every takeoff. So, if your maximum weight based on runway length and the climb limit weight are greater than the maximum takeoff weight from the limitations section, then the maximum allowable weight for that takeoff is the maximum weight from the limitations section. Since the runway limit and climb limit weights are higher, you know that you will not have a problem taking off in that runway distance, nor will you have a problem climbout out after the takeoff.Just remember, the maximum weights in the limitations section have nothing to do with airplane performance. They apply to every takeoff (and landing), regardless of where you are taking off or landing. From a performance standpoint, however, the airplane should be perfectly capable of taking off above those weights as long as you meet the maximum runway and climb limit weights. So, if you want to do a flight test to check the PMDG 737's runway and climb performance, ignore the weights in the limitations section. They serve no purpose in MSFS 2004. If you trying to simulate airline flying, however, obey them (or pretend that you purchased a higher weight option).For your information, the requirement that determines the maximum wieght for a given runway length is that you must be able to safely stop the airplane on the runway after rejecting a takeoff at V1 (without the use of thrust reversers), and be able to continue the takeoff and reach a height of 35 feet by the end of the runway after an engine failure occurring just before V1. (This slightly simplified explanation ignores consideration of clearway and stopway, which we needn't concern ourselves with here.)For the climb limit weights, the airplane must be able to achieve a 2.4 percent climb gradient with the landing gear retracted after a takeoff where the engine failed just before V1.I hope this helps.Don S.

Hi Paul,Happy to see you were inspired to try some flight testing yourself. I think what you found is that the 737-600 is actually not limited by field length on a 5990 foot runway (at least at whatever flap setting the PMDG data is for). For your original flight, the maximum weight that you got from the yellow row in the table is the climb-limited weight, not a field-length-limted weight. It is the maximum weight that will meet the climb requirements (2.4% gradient with the gear up and one engine inoperative in this case) for the altitude and temperature at the airfield.The field-length-limited weight for your flight is around 159,000 lbs, which is greater than both the climb-limited weight and, as you found out from the limitations document, the structural limit weight. In other words, you are limited to a lower takeoff weight by either the structural limit weight or the climb limit weight, not the field length limit weight. (I wouldn't worry too much about the structural limit weight in doing these performance tests, though, since nothing bad is going to happen in this sim if you're above it.)If you're going to test a field-length limited weight for the -600 using the PMDG data that is lower than the structural and climb limit weights, you will need to find a runway that is around 4,000 feet long.Don S.

But did you cut an engine at V1?Don S.

Couldn't agree with you more Tero.In fact, PMDG did a very good job with the performance documentation for their old FS98 757.Don S.

A little more info:The end of each section of the curve before it changes slope is the climb limit (i.e., the maximum weight that meets the climb requirements) for that flap setting. The steeper slope sections are associated with what Boeing calls "improved climb performance." Higher takeoff speeds (overspeeding on the ground) are used at the same flap setting to allow higher weights and still meet the climb performance requirements. Overspeeding rapidly eats up runway length (which is why the curve is steeper), but it will provide more weight capability at a given runway length than going immediately to the next lower flap setting.The Boeing charts are provided on that web site link for several models and engine ratings. I've compared the -700 data with CFM56-7B24 engines at 24,200 lb thrust rating to the PMDG data and they do not match at all.Don S.

There is a certification requirement to demonstrate that the airplane has safe stall characteristics. One of the criteria is that a level wing stall cannot result in more than a 20 degree bank.And the 737NG does not have a stick pusher.Don S.

Hi Robert,It's great to see you post in this thread. You seem to have been responding to my testing at KRNT though you directed your response to Paul. If you don't mind, I'd like to address some of your comments below:>The performance of the airplane and engines is nearly flawless>in terms of performance... The problem you are experiencing>is due to a lack of proper and complete information....Hmm...I don't think so. But then again, I don't expect any MSFS 2004 airplane/engine simulation to be "nearly flawless in terms of performance." But I agree that there is a lack of proper and complete information (as well as some misleading instructions on how to use the information that was provided). As I said in a previous message, however, within certain bounds the PMDG simulation certainly provides a realistic enough feel performance-wise for a good simming experience!>For starters, 5300 feet is a SHORT runway for a maximum weight>takeoff in an airplane of this size. The NG is absolutely>perfectly capable of it- but from an airline captain>perspective- this runway length is "getting a bit hight" on>the pucker scale because there is so little margin for error.What Paul was questioning was the performance at the maximum takeoff weight allowed for the runway length when the runway length limits the takeoff weight and the allowable takeoff weight is from the PMDG documentation. If I, as a captain, am going to trust the PMDG documentation, I ought to be able to show that it accurately portrays the capability of the sim. Unfortunately, for the situation I tried, it did not.>(That's fun in simulators- but in real life...not so fun.... >But hey- it's a sim- so lets have some fun, right?)>>I loaded the airplane to 130,000lbs, and loaded up at KRNT at>standard temperature.>>I had looked at the Runway Limit Weight table and found that I>should have plenty of ability to get off this runway, in spite>of the fact that it would be close.>In other words, you are not at the runway limit weight for that runway. For your scenario, the takeoff weight tables you provide say that the airplane should be able to take off at around 139,000 lbs. So you are not testing the critical case.>As per your scenario, there was no wind- so I ignored the wind>table and continued on... (BTW: If you mess with the wind>table- look it over carefully... the table is actually giving>you output that describes the effect of wind on your runway>lenght...so read the legends carefully because a headwind will>have a lessening effect on your takeoff distance...)>It's a good thing we're using zero wind and ignoring the wind correction table, because the instructions for using the table are wrong. (You cannot take off in 40 knot tailwinds.)I set flaps to 15 because this runway is not long, and>adjusted the trim backward by holding the trim up key for>about three seconds. (forgot to write down the resulting>number, sorry....)What flap setting is the runway limit weight data in the PMDG documentation based on? The trim setting should come from the table in the takeoff data document, not just be arbitrarily set.>>Released the brakes and opened the throttles for a max N1 of>93.x%. >>Thrust set, everything looks good... V1... Rotated at 3>degrees per second and was climbing through 400 feet be the>time i cleared the end of the runway.....>>Now.....>>If you try this procedure at flaps 10- you get much closer to>the end of the pavement.... Flaps 5 and you might be>swimming.....With all engines operating, I don't think you will have a problem even with flaps 5. The maximum runway length limited takeoff weight is based on failure of an engine just prior to V1. Did you try continuing the takeoff with an engine failure (at the maximum weight for that runway length and environmental conditions)?>>(BTW: Rejected the takeoff on the flaps 15 just for fun- and>had no problem stopping before the end. Would have qualified>for a brake inspection- and more than likely would have melted>a tire plug....)>I was also able to successfully reject the takeoff for your scenario. However, as you noted, you were not at the limiting weight. I was unable to avoid going into the drink at the limiting conditions of 136,600 lb at 79 degrees F at KRNT using flaps 15 on the 737-700. (BTW: You don't get to use reverse thrust for this test as the field length limits don't include it.)>So how did i select flaps 15 instead of 5? Experience and a>but of guesswork....>And because the takeoff data provided in the PMDG documentation does not indicate what flap setting it is for. Actually, the best flap setting for your scenario would have been flaps 25.>In the real world, we have dispatch offices who provide very>detailed tabular data for every runway you will operate on/off>of. The tabulated data will suggest flap configurations and>"balanced field length" data to ensure that V1 will occurr>within stopping distance of the end....>>If it is put into printed form- this type of data for a small>airline can run over 1000 pages.... and obviously it varies>by every airport and runway- so there is simply no way to>compile it and provide it to MSFS users....The level of detail you are describing is unnecessary for MSFS users. However, tabulated data can be provided in a much more abbreviated format similar to what was provided in the PMDG documentation. All that would be needed would be to augment it by providing separate tables for each takeoff flap setting and a small set of different airport elevations. Users can then approximate or interpolate for specific runways (i.e., play dispatcher!). Otherwise, why provide any data at all? Maybe it would have been better just to provide the general guidance that you provide below.>>(The data service from companies like Jeppesen costs many>hundreds of thousands of dollars....)>>So there really is no "hard and fast" information to tell you>what flap setting to use- but I have used the following>guestimates when testing this airplane:>><6500: Flaps 15>6500-7500: Flaps 10>7500+: Flaps 5>>You will find that each airplane behaves a bit differently, so>you can get away with lower flap settings in the 700 than in,>say, the 900!>>A great fun experiement is to fly the same departure in each>of the airplanes and see how different they accelerate, rotate>and climb away....>>Oh- on a side note: The V1 listed in our tables is a>"balanced field length assumptive V1." By this, the V1 figure>assumes that "all other things being equal, a balanced field>length will exist to accelerate to V1 and stop on remaining>runway." Obviously- if you were flying a 900 out of KRNT,>you wouldn't want to load the airplane to max takeoff weight>because you will certainly go swimming after V1 but before>rotation.... In real life- a dispatcher (or detailed book)>would tell you that!>But you can load the airplane to the maximum takeoff weight allowed for the KRNT field length. And the data in the PMDG documentation implies that you can use it to determine the maximum takeoff weight that will keep you from swimming. If not, what was the purpose for including it?>So- next time you wander through airline ops: Hug your>dispatcher.... ;-)>That's for sure! :-)

Hi Paul,I tried one quick takeoff out of Renton Municipal Airport (KRNT) in Renton, WA. The runway is 5382 feet long. Using the 737-700, I loaded it up to about 136,700 lb. for an OAT of 79 degrees F (26 degrees C). Using flaps 10, the V speeds were around 122-124-132 (within a knot anyway - I let the FMC fill them in, but forgot to write them down), and N1 for a full rated takeoff was 95.5%. I used a trim setting of about 7 3/4.I ran the engines up to full thrust with the parking brakes set, then let 'er rip. I reached Vr well before the end of the runway and lifted off with pavement to spare. I don't know how it would have done in an engine out situation, or even if the PMDG takeoff weight tables are for flaps 10 (I doubt it and agree with you that they are probably for flaps 5), but at least I was able to successfully complete this takeoff.Hope this helps.Don S.