July 20, 201411 yr Our whole fleet has 10.8. We could takeoff with VNAV armed but we don't by company policy. It was explained to me that there is something in 10.8 that can cause the predictive windshear alerting to be inhibited if VNAV is armed prior to takeoff. Is it because of this? During airline simulator evaluations of FMC Update 10.8A, an unintended consequence of arming VNAV for takeoff was discovered with respect to the windshear escape maneuver. If VNAV is armed on the ground, it will remain armed even if TO/GA is pressed below 400 feet AFE in accordance with the windshear escape maneuver. At 400 feet AFE, VNAV will engage and windshear guidance will be lost. TO/GA must be pressed a second time when above 400 feet AFE in order to regain the appropriate windshear guidance. This condition exists on FMC Update 10.7, 10.8 and 10.8A. Arming VNAV on the ground is not permitted prior to Update 10.8. Matt Cee
July 20, 201411 yr Author Question matt in real life when you are connected to the ground when do you say you are cleared to disconnect and go to hand signals? I'm using fs2crew and i'm never sure when to say this. Also when to call for T/O flaps? after the ground crew have disconnected? What is your call on this matt... Vernon Howells
July 20, 201411 yr Is it because of this? During airline simulator evaluations of FMC Update 10.8A, an unintended consequence of arming VNAV for takeoff was discovered with respect to the windshear escape maneuver. If VNAV is armed on the ground, it will remain armed even if TO/GA is pressed below 400 feet AFE in accordance with the windshear escape maneuver. At 400 feet AFE, VNAV will engage and windshear guidance will be lost. TO/GA must be pressed a second time when above 400 feet AFE in order to regain the appropriate windshear guidance. This condition exists on FMC Update 10.7, 10.8 and 10.8A. Arming VNAV on the ground is not permitted prior to Update 10.8. That would be it. That's the best explanation I have read, thanks.
July 20, 201411 yr Question matt in real life when you are connected to the ground when do you say you are cleared to disconnect and go to hand signals? I'm using fs2crew and i'm never sure when to say this. Also when to call for T/O flaps? after the ground crew have disconnected? What is your call on this matt... After pushback is complete and the tug driver tells us to set our brakes, we'll tell them to disconnect and go to hand signals. After we get the wave-off from the ground, crew, we'll call for flaps. Matt Cee
July 20, 201411 yr Our whole fleet has 10.8. We could takeoff with VNAV armed but we don't by company policy. It was explained to me that there is something in 10.8 that can cause the predictive windshear alerting to be inhibited if VNAV is armed prior to takeoff. In addition to Spin's explanation, the official text is in the Bulletin Record chapter of your company FCOM1. We have 10.8A and normally arm VNAV on the ground, If windshear is a possibility, then I don't arm VNAV.
July 20, 201411 yr Author Thanks matt. Once all ground crew are clear then you can extend flaps so you don't cause injury to equipment or crew is that the reason? Also when to ask for clearance prior to departure? Am i right in looking up general notices in navigraph and it tells you there for example 15 mins before EOBT? Vernon Howells
July 20, 201411 yr In addition to Spin's explanation, the official text is in the Bulletin Record chapter of your company FCOM1. We have 10.8A and normally arm VNAV on the ground, If windshear is a possibility, then I don't arm VNAV. We don't have anything in our manuals that talks about it. We switched from the Boeing manuals to company tailored ones last year and a lot of stuff that isn't specific to our operation got pulled out. They don't let us arm VNAV on the ground anyway so no need to clutter up the books.
July 21, 201411 yr I think most US pilots haven't heard of FCOM 1 & 2. The companies have a history with their own manuals and rename and edit the Boeing provided sources for their own tribal sensitivities. Matt Cee
July 21, 201411 yr We don't have anything in our manuals that talks about it. We switched from the Boeing manuals to company tailored ones last year and a lot of stuff that isn't specific to our operation got pulled out. The companies have a history with their own manuals and rename and edit the Boeing provided sources for their own tribal sensitivities. There's a lot at our place who wish our company would do the same thing because of endless discussions on how to interpret the Boeing's wording.
July 22, 201411 yr I think most US pilots haven't heard of FCOM 1 & 2. The companies have a history with their own manuals and rename and edit the Boeing provided sources for their own tribal sensitivities. I haven't seen a FCOM since I flew an ATR a long time ago. The translation from French to English was, interesting to say the least.
July 23, 201411 yr Hi, if you apply noise abatement procedure 1, (flaps retraction at 3000 ft AGL) you have to Select VNAV after flaps retraction, with flaps down you"ve to Select FL CHG as Vertical mode. ciao Andrea
July 23, 201411 yr Hi, if you apply noise abatement procedure 1, (flaps retraction at 3000 ft AGL) you have to Select VNAV after flaps retraction, with flaps down you"ve to Select FL CHG as Vertical mode. ciao Andrea I've never used that technique. Where did you come across that? Matt Cee
July 23, 201411 yr "Maintain a minimum of V2 + 15 knots during initial climb. At light gross weight a higher speed (up to V2 + 25) may be selected, to synchronize F/D pitch command and avoid objectionable body attitude. Do not exceed 20 degrees nose up. Monitor engine instruments and cross– check flight progress. Above 400 feet, call for appropriate roll mode, if required. Verify proper mode annunciation. Select/verify roll mode. Verify proper mode annunciation. Verify flight mode annunciation. At 1,500 feet AAL, verify the FMA displays N1 and select CMD A or B. Call “COMMAND A or B.” At 1500’ AAL, verify automatic thrust reduction to climb thrust. At 3000 feet AAL call “BUG UP” and set the airspeed bug to “UP.” Retract flaps on schedule. Position FLAP lever as directed and monitor flaps and slats retraction. Call “FLAPS UP, NO LIGHTS.” Above 3,000 feet AAL, engage VNAV or select normal climb speed and verify annunciation. Verify proper mode annunciation. Call “AFTER TAKEOFF CHECKLIST” when flaps are up. Position landing gear lever OFF, engine start switches as required. Verify air conditioning and pressurization are operating and configured normally with a positive pressure differential. When conditions permit, release the cabin crew and switch" Hi, I'm applyintg the technique for NADP1 climb profile as taken by the SOPs of an important airline using B737NG .... Best Regards Andrea B.
July 23, 201411 yr "Maintain a minimum of V2 + 15 knots during initial climb. At light gross weight a higher speed (up to V2 + 25) may be selected, to synchronize F/D pitch command and avoid objectionable body attitude. Do not exceed 20 degrees nose up. Monitor engine instruments and cross– check flight progress. Above 400 feet, call for appropriate roll mode, if required. Verify proper mode annunciation. Select/verify roll mode. Verify proper mode annunciation. Verify flight mode annunciation. At 1,500 feet AAL, verify the FMA displays N1 and select CMD A or B. Call “COMMAND A or B.” At 1500’ AAL, verify automatic thrust reduction to climb thrust. At 3000 feet AAL call “BUG UP” and set the airspeed bug to “UP.” Retract flaps on schedule. Position FLAP lever as directed and monitor flaps and slats retraction. Call “FLAPS UP, NO LIGHTS.” Above 3,000 feet AAL, engage VNAV or select normal climb speed and verify annunciation. Verify proper mode annunciation. Call “AFTER TAKEOFF CHECKLIST” when flaps are up. Position landing gear lever OFF, engine start switches as required. Verify air conditioning and pressurization are operating and configured normally with a positive pressure differential. When conditions permit, release the cabin crew and switch" Hi, I'm applyintg the technique for NADP1 climb profile as taken by the SOPs of an important airline using B737NG .... Best Regards Andrea B. Hmm. I don't seen where it tells you to go to LVL CHG before flaps are up. flaps down you"ve to Select FL CHG as Vertical mode. Matt Cee
Create an account or sign in to comment