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mfor

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mfor last won the day on September 3 2017

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About mfor

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  1. mfor

    Simples question....

    That doesn't work for me with IXEGs FMC unfortunately. You can reenter the speed restriction after clearing all restrictions on the legs page of course by leaving the alt parameter blank e.g. 220/
  2. mfor

    Simples question....

    Pressing the DEL (delete) button and then the button right to the restriction you want to remove, works for me.
  3. mfor

    Question on flaps

    Well those numbers refer to the maximum flap speeds - you can deploy the flaps at those speeds if you need the drag, but in most cases you'd deploy them later. As long as you do not bust any speed restriction (ATC or Vspeed) I think it's fine. The FMC target speed on descend is kind of a lower limit, i.e. the AT will increase the throttle if the speed falls below that speed minus 10 knots. You can use the AP in speed/vs mode though to plan your descend manually - which is not unheard of in real life as well, especially since ATC will give you vectors and possibly altitudes that deviate from a preplanned STAR approach every now and then.
  4. mfor

    Help with cruise speed

    The mach number is an indicator for the aerodynamic regime you are in. It is expressed as fraction of the speed of sound in the air you are currently surrounded by and for sub sonic flight you'll want to stick below 0.8 or whatever number the manufacturer has set. The speed of sound does not change with pressure , so the mach number does not drop as you increase altitude - it does change somewhat with temperature though. For the 733 it mainly serves as ceiling that you do not want to cross. The true airspeed (TAS) is the speed at which the aircraft is moving relative to the surrounding air and can be calculated from the indicated airspeed IAS and the altitude. It is however not that important to the actual flying, since the behavior of the plane depends on the forces the air exercises, not its actual speed - as long as you don't change the aerodynamic regime. If you go from subsonic to trans/supersonic the forces change dramatically. If you combine the true airspeed with the motion of the air relative to the ground you get the ground speed, which is only important during landing/takeoff and for navigation. These days ground speed is usually provided by GPS. The (calibrated) indicated airspeed (cIAS) is the speed that is displayed on the instruments and derived from the pressure difference between the moving air (at the current speed) and the static pressure. I like to think of the (calibrated) IAS as "aerodynamic speed" because it determines the forces that the flowing air applies to the aircraft, i.e. as the air gets thinner you need to go faster (the true airspeed is higher) for the same amount of force. When it comes to flying this is the most important speed, because it tells you how the aircraft will behave: if it is low you need a large angle of attack too keep the aircraft level and are in danger of stalling if you go slower. If it is high the aircraft will be very responsive to control input and you might exceed the allowed forces of the air frame if you speed up further. The FMC in the 733 will track the IAS setting as long as it does not exceed the selected mach number. So at low altitudes you will be at 280 knots IAS and as you climb higher your true airspeed needs to go up to keep the IAS at 280 as the air gets thinner and at some point you will reach a speed that equals mach 0.72. At this point the FMC will track the mach number instead and basically keep your true airspeed more or less the same (the speed of sound will change with temperature) while the IAS drops as you get higher because the pressure goes down. On descend this is reversed: you will fly at mach 0.72 until the IAS reaches 280 and then the FMC will reduce the TAS during your descent to keep the IAS at 280. Here's a quick table of the corresponding speeds in a standard atmosphere: Altitude IAS TAS Mach Mach TAS IAS 0 280 280 0.42 0.72 476 476 10000 280 323 0.51 0.72 402 460 20000 280 375 0.61 0.72 442 333 30000 280 437 0.74 0.72 424 271 35000 280 473 0.82 0.72 415 242 40000 280 521 0.91 0.72 413 215 To get the ground speed you simply need to add the current winds to your TAS (as vectors). Looking at that table during the climb you aircraft will stay at 280 knots up until roughly FL300 - you TAS/GS will have gone up from 280 to ~437 at that point. (More precisely you'll reach mach 0.72 at 28500 where your TAS is 427.) Climbing further will cause the speed to stay at mach 0.72 and your IAS will drop to 215 at FL400 whereas the TAS/GS will only decrease slightly due to the temperature changes.
  5. Unfortunately the current implementation of the editing the route causes rapid creation and execution of new code which any anti virus program will check before execution and this is slowing down the whole sim. As of now the only workaround is to exempt the x-plane folder from live scans in the settings of your AV program. For Windows Defender you can find instructions on how to set up an exclusion at https://support.microsoft.com/en-us/help/4028485/windows-10-add-an-exclusion-to-windows-defender-antivirus
  6. mfor

    LNAV and Direct to

    Thank you - a few follow up questions if I may. Does that mean whenever there is a previous way point in the flight plan the plane will try to return to the path otherwise use the shortest path (unless an inbound track is set ofc)? Is the plotted line attached to the aircraft in the latter case?
  7. mfor

    LNAV and Direct to

    I don't know what a real 733 does but I think that's the way it should work. After all you command a certain path/track from your current location to the destination. Now due to limitations of how fast the aircraft can turn you end up outside of that track. So the FMC has two choices Fly the shortest way to the destination (green) but depending on how far off track you are, you may fly into areas you're not supposed to - imagine an obstacle on the green line Return to the commanded track on the shortest route (red) - that way you "overshoot" your heading temporarily but after that you fly on the commanded track (gray) Now obviously during normal flight the offset from the commanded track will be minimal, so 1) is the less confusing option but I think if you are serious about following the commanded flight path 2) is the correct choice. Similar to following the localizer or glide slope where you absolutely DO want to return to the correct path instead of aiming for the shortest path to the target. Activating the route twice helps in that case, because you basically set a new commanded path - ideally at the point where red and green diverge with the green path becoming the new path the aircraft will follow.
  8. mfor

    need help

    IIRC the version is displayed at the bottom of the window that slides in when you move your cursor to the left of the screen. If you've just downloaded it you should have the latest version and you usually get an email if an update is available.
  9. mfor

    need help

    Well it's modeling the real world behavior where the spot lights to illuminate the logo are situated in the little tails at the end of the wing. Since the winglets replace those you cannot have both logo lights and winglets at the same time (IRL and IXEG). Also 737-300s leaving the factory did not have winglets and when retrofitting them they (usually?) keep the switches as they were and just stick an INOP sticker on them. So IXEG is following real world practice here.
  10. mfor

    Strange buzzer at startup

    Do you have the IRS systems turned on by chance - that causes a buzzing sound for me. FWIIW you can turn on standby ac power which will feed AC to the left IRS (but drain the battery) and allow you to align it without the buzzer. The right IRS will turn itself off after 5? minutes without AC anyway.
  11. mfor

    FMC-Freezing Bug

    It's not about defender: any anti virus program would have to check the executable code the FMC is generating rapidly - so pretty much any virus program should trigger this. For some reason the forums here are moderated in a way to make it look like it's a problem specific to defender, when it really is about how the FMC calculates the routes on the fly, as all virus programs have to check those newly created files for viruses (how else would they know it's safe). So you need to make an exception for this in pretty much any AV program to prevent those freezes from happening, until IXEG can fix things on their end.
  12. The pressurization system has 2 (semi) automatic modes of operation: 1) Automatic - you set the FL and the destination altitude and the system will capture the take-off altitude and return to that level on a aborted climb and target the destination altitude for a normal descend. 2) Standby - you set the desired cabin altitude and can also make manual adjustments - this is useful for non standard flights, e.g. touch and go training. There are also two manual modes (AC and DC powered) where you control the opening of the outflow valve manually - this is for emergencies only (e.g. when ditching you'd close the valve manually to prevent flooding and turn off the bleeds to still allow de-pressurization) The flight/ground switch will activate/deactivate the system, however it will also automatically engage when there's no load on the wheels. For normal flights you would use automatic entering FL and destination altitude. I think it's also part of the procedure (may depend on operator) to set the cabin altitude to 200 below field elevation, so in case you quickly need to switch to Standby the plane will be fully de-pressurized when landed (the auto system handles that automatically afaik). As for the bank angle I think I remember someone (Litjan?) saying it should be lower at high speeds, however IIRC LNAV will disregard any limitations to follow the route.
  13. mfor

    Take-Off Flaps setting

    On Sunday evening it landed at the small Taney County airport, seven miles (11km) away from Branson, Missouri. Passengers on board the Boeing 737-700 reported an abrupt landing as the large plane touched down on the 3,738ft (1,140m) runway. http://www.bbc.com/news/world-us-canada-25717016 Well, they probably needed flaps 15 for takeoff - and a new pair of pants
  14. Well they kind of have - not on a 737-300 though, I suppose. SCNR
  15. mfor

    Anti Ice

    What you can do though is put the switch in the ground test mode for some time. This will operate the wing anti-ice on the ground. If you do that right before takeoff you can free your wings of ice just long enough for a takeoff and let the normal operation take over once airborne - in heavy icing conditions you might have to go twice through the maximum operating time or even press it while accelerating down the runway. As for running it on the ground - ours is apparently an early model: "Note that on early systems, i.e. those with a GND TEST position, with the WAI switch ON on the ground, the WAI is inhibited until lift-off i.e. 'armed', This is opposite to the present system." http://www.b737.org.uk/iceandrain.htm
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