LuckyFlyer Posted October 27, 2015 Share Posted October 27, 2015 I use the freeware 777 models(POSKY from Simviation. I use the FMC and set it up correctly. However, I notice that upon crossing a waypoint, the speed drops down even though the speed I have set in the FMC is much higher. Most of the time, it drops to 200 knots. What am I doing wrong? I have set up the FMC correctly. SOmetimes, this speed drop is random i.e occurs between two waypoints. Link to comment Share on other sites More sharing options...
napamule2 Posted October 28, 2015 Share Posted October 28, 2015 Pitot Heat? Shift+H. Chuck B i7 2600K @ 3.4 Ghz (Turbo-Boost to 3.877 Ghz), Asus P8H67 Pro, Super Talent 8 Gb DDR3/1333 Dual Channel, XFX Radeon R7-360B 2Gb DDR5, Corsair 650 W PSU, Dell 23 in (2048x1152), Windows7 Pro 64 bit, MS Sidewinder Precision 2 Joy, Logitech K-360 wireless KB & Mouse, Targus PAUK10U USB Keypad for Throttle (F1 to F4)/Spoiler/Tailhook/Wing Fold/Pitch Trim/Parking Brake/Snap to 2D Panel/View Change. Installed on 250 Gb (D:). FS9 and FSX Acceleration (locked at 30 FPS). Link to comment Share on other sites More sharing options...
Rupert Posted October 28, 2015 Share Posted October 28, 2015 Pitot Heat? Shift+H. Chuck B +1 Being an old chopper guy I usually fly low and slow. Link to comment Share on other sites More sharing options...
LuckyFlyer Posted October 30, 2015 Author Share Posted October 30, 2015 Tried everything, nothing works. With this, I manually need to adjust the speed after every waypoint. Any other suggestions? Link to comment Share on other sites More sharing options...
MBKHOU Posted October 31, 2015 Share Posted October 31, 2015 I don't know for sure as I don't have that plane, but it's likely that the FMC is not full functioning. IE: some free jets use a freeware FMC which is not realistic at all when used with a Boeing jet. Are there actually speed restrictions for those waypoints, or does it just get a wild hair and change speed for no good reason? Are these waypoints at high or low altitude? IE: high alt speeds should be mach speeds and not IAS. Link to comment Share on other sites More sharing options...
LuckyFlyer Posted November 1, 2015 Author Share Posted November 1, 2015 I am not that knowledgeable about this but I do use the High altitude option in the FSX Flight planner and the speed setting in the 777 is in IAS. Could that be the cause? If so, what route planning option allows me to fly in IAS? Link to comment Share on other sites More sharing options...
MBKHOU Posted November 1, 2015 Share Posted November 1, 2015 I am not that knowledgeable about this but I do use the High altitude option in the FSX Flight planner and the speed setting in the 777 is in IAS. Could that be the cause? If so, what route planning option allows me to fly in IAS? The FSX flights won't effect the FMC in the plane. Totally separate. The high vs low in the planner chooses between the low alt enroute, vs the high alt enroute plans/waypoints/fixes. Or I think anyway.. The FMC runs whatever plan you punch into it. You don't normally need to worry about speeds in the FMC unless you have speed restrictions for waypoints/fixes. And most all of those will be at lower altitudes under FL180, where IAS is used. The change from IAS to mach speed or visa versa is automatic, and both speeds should be shown in the FMC assuming the 777 FMC is about the same as the 737. Say I use a certain cost index and the FMC decides to climb out at 300 knots, and the cruise mach speed will be .79. When 300 IAS merges with mach .79, the FMC should switch, and also you should see the change on the PFD. And visa versa on the descent. When you start the descent, it will be at mach .79, but as you merge with IAS 300 knots, or whatever speed the FMC decided, it will switch to IAS on both the FMC, and the PFD. One almost never cruises with IAS. Even if at a fairly low altitude for cruise, the FMC will usually switch from IAS to mach speed. IE: when I fly a short route where the cruise alt is low, say FL220 as in the case of KHOU to KAUS, when I get to FL220, the FMC and PFD will switch to mach speed, which will be pretty low.. Say mach .66, or whatever.. Much lower than any flight long enough to let the plane climb to it's normal fairly high altitude and mach speed for cruise. " IE: say mach . 79 at FL390 or whatever. The FSX plan has nothing at all to do with any of this. edit..btw, the automatic switching would be in VNAV. But if flying the vertical path semi manually, you will have to switch from IAS to mach or visa versa manually. But the FMC should still show both speeds whether VNAV or manual. IE: say I'm at FL390, and I decide to descend using vertical speed. In that case, when the mach speed of .79 merges with the 300 IAS, I will have to switch from mach to IAS myself using the MCP. Link to comment Share on other sites More sharing options...
LuckyFlyer Posted November 26, 2015 Author Share Posted November 26, 2015 Whenever I use the Honeywell FMC, this problem occurs. However, when I use the JB777 panel FMC, there is no speed drop. Works perfectly except I have to change altitude manually. The FMC does not trigger an altitude change when I reach waypoints on my way to cruise altitude. I will try a few flights and see what works. Thanks for the help guys. Link to comment Share on other sites More sharing options...
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