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Guest GabrielR

Question RE: Take off

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Guest GabrielR

Hi guys I need confirmation on my TO Procedures:I am going to describe the ICAO A procedure for TO (noise Abatement) TO Flaps: 5, Weight Less than 117K Pounds.1. advance the throttles to 40%2. Advance the throttles to 70% Click TOGA3. Call Airspeed alive, 100 knots v1-Rotate4. Rotate the AC at +-3 deg per Sec up until 15 Deg (It has proven to be dificult for me)5. Call Positive Rate - Gear Up6. Follow the FD (WIngs Level/V2+20)Up until here it was a very straight forward here comes the deal:7. at 400' AGL select roll mode, HDG or LNAV (Why?, I am still flying the AC manually, Roll mode will no be in effect if the AP is off) ---> is this just to have the FD cue of the route?????8. at 1000' Engage Autopilot (This will activate vertical navigation Mode on LNAV) I will still be flying at V2+209. 3000' AGL I have two Options: 9.1 Continue the climb in HDG/LNAV-LVLCHG: 9.1.1 Set Speed bug to 250 9.1.2 As the Spped passes 180 (VM5) Select Flaps 1 9.1.3 As the Speed Passes 190 (VM1) Select Flaps Up 9.2 Continue the Climp in HDG/LNAV-VNAV 9.2.1 Select Flaps 1, when VM1 Select FLaps UpIs this right? My main problem here starts Just after Rotating (Trim Usually around 5, as per FMC)I got to V1, Rotate, While I am rotating the AC the Speed Keeps going up very fast so I Always finish the rotation with a speed higher than V2+20, in order to recapture the speed I have to over rotate the AC, sometimes up to 28 Degrees! Imagine the faces of my PAX!!!Going to keep on practicing, I guess I am rotating too slowly and Allowing the AC to increase their Speed.If someone has any observation, please let me know.

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Guest hlm65

Hi,regarding some of your points:7-you would like to have a roll mode selected even flying manually for 2 reasons: first you'll get F/D correct roll guidance and second you'll have your selected roll mode engaged as soon as you engage the A/P8-you should have already selected a pitch mode before engaging the A/P: if you select VNAV, the FD bars will drive you to command the correct pitch attitude to maintain V2+20 till the acceleration altitude and then to achieve the standard 250 kts climb speed up to 10000 ft9-regarding flaps retraction schedule, it depends on weight and is not fixed.As standard practice, many airlines recommend to clean the airplane and then engage A/P. You can retract flaps lower than 3000 ft: I normally get the airplane clean at about 2000 ft and then engage AP. But you can engage the AP at 1000 ft and progressively clena the plane.Regarding speed build up during rotation: be careful not to overrotate (tailscrape !) and let the speed increase over V2+20 if to avoid this you have to get an abnormal nose up.Regarding trim settings: it seems that 5.5 as shown in the FMC is too much (I think the FMC in the PMDG doesn't model trim settings).The Airplane Flight Manual states, for example, (for the -700 series) that for a Flap 5 takeoff the following are the stab trim settings at at to weight of 140000 lbs:3 3/4 for CG at 33 % MAC4 1/2 for CG at 30 % MAC4 3/4 for CG at 28 % MAC5 1/2 for CG at 24 % MACWe should have a "virtual despatcher" that gives us these infos !Hope this helps.

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Guest frankathl

Nice post, Enrico!"We should have a "virtual despatcher" that gives us these infos !"We will as soon as Mats is ready to give it to the world :-)BR,Frank

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Guest boxjockey99

This is coming from a -300 series driver so I agree some things are different but in the main this is the way we do things!1) Advance to 40% then hit TOGA (70% is not normally used unless in icing conditions)2) call 80kt (this is the point beyond which you only stop the take off for a fire, eng fail, blocked runway, loss of control or takeoff config warning.3) call V1 & Rotate, rotate at 3 deg / sec to avoid tailscrape, 4) +ive rate - Gear up5) pitch up with the F/D to the commanded pitch and roll. note F/D in TOGA will pitch for a speed of V2 to V2+20. If you exceed V2 +20 it will pitch up to bring you back to V2+20, If you are below V2 it will pitch down to bring you to V2. If you are somewhere in the middle it will pitch to maintain the current speed. Make sense? so your problem with pitch is because the F/D is trying to get you back to V2+20, it will then pitch down to maintain V2+206) 400ft roll mode engaged, this means your F/D will command roll to follow either HDG SEL bug or the LNAV path depending on yourt mode. If you don't do this then you will continue in wings level and not follow the SID!7) 1000ft this is the min alt for A/P engagement it is not mandatory to put it in at this point, you are allowed to fly this aircraft unlike the Airbus!Flap retraction comes in 2 flavours in the UK1) standard is 400ft LNAV mode engaed, 1000ft VNAV or LVL CHG and accellerate retracting flap on schedule. This is for airfields with no noise restrictions. 2) ICAO noise, maintain TOGA mode with V2+20 till 1500ft Above the airfield then select N1, this reduces the power to CLB and opens the speed window at the current speed. Maintain the speed until passing 3000ft above the airfield then select VNAV or LVL CHG and accellerate retracting flap on schedule. This is for many major airfields with noise restrictions. THe 737NG is a slippery beast and does like to accellerate quickly but you just need to be ready for that. If you end up exceeding V2+20 there is no problem. The main reason you have the V2+20 function is for when an engine fails. In this situation you will need all the energy you can muster so you sacrifice speed for climb rate back to a min of V2 (safe climb speed). if you were faster than V2 + 20 when the engine fails you have all that extra energy to use as a climb (a luxury). The F/D will pitch for the V2+20 regardless of pitch angle and it is normal for it to pitch for 25deg+ but I think Boeing recommend not pitching past 20deg (not sure if that is a company thing or a Boeing thing).As an example I took an aircraft to Romania for maintenance (C Check) so we had no seats in the aircraft and only minimal fuel. We reduced thrust to 54 degress Celcius (max) and still climbed like a homesick angel. The F/D was giving cues of 30 degrees plus which in this case you must follow or you will accellerate through flap limiting speeds while climbing! Jolly good fun but just goes to show you need to be aware of many things especially in abnormal circumstances!Hope that helps, please feel free to ask more questions if you think I can helpregardsKris

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