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Guest Nick Bartolotta

737 FMC & V-speeds

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Guest Nick Bartolotta

Hi folks,I've got two questions about the PMDG 737-800...1) How can I go "Direct To" a waypoint on my route? I have searched the forums for this but haven't been able to find an answer. Is there a way to do this in the FMC? 2) Before takeoff, I fill in all my information in the PERF page, and I go into my takeoff page (on the FMC). I then put in my flaps setting for takeoff, and it fills in the v-speeds (V1, Vr, V2) when I click on them respectivly. However, when I am taking off, and I hear "rotate" being called out (indicating I've reached Vr), and I rotate, the aircraft still seems like it doesn't have enough speed built up, and then when I hear V2 being called out, then the plane seems to actually rotate. To my knowlage, I always thought Vr was the speed where you begin to raise the nose, and V2 was the safety speed in the air...but it doesn't seem like this.Thanks in advance. Fly safe,-Nick Bartolotta

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1)Use the Legs page. If the fix is already in your flightplan path, and ATC is giving you a shortcut (for example) to a fix ahead; just click the LSB next to the fix and then click the top LSB and execute. Otherwise, enter the fix name in the scratchpad area and enter it by clicking the top LSB and execute. It's possible I've not answered your question, I assumed you already had a flightplan and were enroute.2)Check your trim. If the trim is set too low (it defaults on too low in my setup) it will seem like the plane is sticking to the ground.


Dan Downs KCRP

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Guest tomahawk_pa38

Dan,Thanks for that bit of info - I've always had trouble taking off from Southampton (EGHI) - I nearly always hit the landing lights yet IRL, 737's use this airport all the time. I thought that once you loaded the aircraft, the trim set itself automatically - bit basic eh ? I think I thought this because whenever I've tried changing the trim on the default 737 - it always changes itself - doh !

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Guest Nick Bartolotta

Thanks for the response Dan!I am still a little confused about the first question...where is the LSB on the Legs page (image below for example)http://img386.imageshack.us/img386/8748/fsscr0107xa.jpg[/img]I'll give the trim a try next time I takeoff, I too thought it automatically had it setup.Thanks again, -Nick

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trim on take off always catches me out.On my last flight i had a trim setting from the FMC of 5.50 - it is really hard to see the numbers on the throttle so i entered it way past 5 and i still had an issue rotating. seems to be very slow and heavy on take off. My trick is normally to add a bit more trim than what the FMC states


Paul McMahon

Ireland

747400.jpg

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Guest Clansman

>Thanks for the response Dan!>>I am still a little confused about the first question...where>is the LSB on the Legs page (image below for example)>>http://img386.imageshack.us/img386/8748/fsscr0107xa.jpg[/img]>>I'll give the trim a try next time I takeoff, I too thought it>automatically had it setup.>Thanks again, >-NickHi Nick,Here's my attempt to explain:Dan referred to LSB - I assume he meant Line Select Button. Anyway, if ATC cleared you directly to TOUCH, in that particular FMC page, you'd push the LSB just left of TOUCH (which transfers the word TOUCH into the scratchpad) and then push the LSB just left of SWABE (which copies the scratchpad content into that particular position), effectively tranferring the TOUCH waypoint into the top of the page (hopefully erasing both SWABE and HILTI.Your FMC now heads you onto TOUCH and there you go.Of course I may be wrong, in which case any corrections are welcome.Cheers,Pedro Venda.

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Guest Nick Bartolotta

Okay I tried that and corrected the trim according to the FMC, and it worked! Thanks everybody for the speedy responses and help! :)

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how do you correct the trim, i know where to find the TRIM in the FMC but how do you set it?

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Bring up the throttle window by clicking T, the trim indicator is on the left side of the throttles. It is controlled by either buttons configured on your joystick for that purpose of keys on the number pad with NumLock off: the 7 key is nose down (decrease trim angle) and the 1 key is nose up (increase trim angle). The sim makes a wratcheting noise when the trim motor is running.Good pilot technique when hand flying is to use the trim for all small pitch adjustments. The keys are repeaters, that is, when you hold the button or key down it repeats like the brake key. I have set the repeat rate in FS9 to half of it's default range to prevent over controlling when handflying.


Dan Downs KCRP

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Guest tomahawk_pa38

Tried taking off from EGHI again (runway 20) and even with the trim set to nearly 10, I still took the landing lights out. I don't achieve V1 until about 3/4 down the runway and V2 at the touchdown point of runway 02, just lifting off as a I plough through the lights. Anyone any suggestions please ?

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Guest isagani67

Hello Dave,Check your fuel load maybe it's to much for that flight. How long is the runway? Set flaps 5. Use Club 1 T/O speed ( Club 2 & club 3) are meant for long runways and heavily trafficked airports but requires more speed to lift off.What joystick you are using. I am using saitek X52, the technique is when 80 knots is called out pull back your joystick; trim up to 10-15 degrees; at 100 knots release it slowly then pull it back after v1 is called out sure you will have a smoth take off.My average take off speed v1=134 Vr=146 v2=154-160Regards,I FORGOT TO REMIND: INCREASE THE THE POWER TO 46% BEFORE RELEASING THE BRAKE. It will accellerate you faster.

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Guest tomahawk_pa38

Hi Thanks,Runway is 1800 m approx, last time I checked fuel all the weights were within limits but i'll check again. I set flaps 5 - maybe I try 10 next time.What do you mean by Club 1/2/3 do you mean derates as I don't d-rate the thrust as i've got enough problems already.My joy stick is also a Saitek but can't remember which one (I'm at work).My V speeds from memory I think left me with V2 at 147 (737 - 700.I hadn't thought to trim as high as 10 - 15 I thought 5 - 7 was the norm and I haven't tried pulling back on the joystick at 80 kts - I usually wait for the Rotate command. I will also try powering - up on the brakes as you suggest.I'll see what hapens next time.

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Guest 102301636

It's standard to check that both engines deliver equal and proper power prior to the takeoff roll...set the engines to 40% before applying TO/GA or manually applying take-off thrust...also according to Boeing you should maintain a firm nose down pressure on the yoke to ensure good tire contact with the runway to prevent the aircraft from the leaving the runway until VR...only at VR should you begin to raise the nose...also check out PMDG documentation on take-off procedure if you follow it to the line you should not have any problem, the aircraft handles as it does in real life (pretty much)as a sidenote, you state that you are within the weight limits of the aircraft, that may be all well and good but are you within the weight limits of the aircraft given the environmental/meteorlogical conditions at the airport and runway length?take a look at your joystick also, check the null zones and calibration to see that everything is okhope this helps

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Guest isagani67

Good morning Dave,Yes its a bit worrying to T/O from Southampton. There is a residential area in elevated ground right infront of your horizon. I took off from that Airport last night and just make a turn to EGLL its quite nervous. You are right, I meant derrates and correct me for club3 (its CLUB; CLUB1; CLUB2). Alan of PMDG posted as per BOEING T/O procedure is to keep the nose down until Vr while the technique I suggested to you is from my AIRBUS procedure which I found it working well with BOEING. I don't know if he is referring to fully automatic T/O had not tried it so far. I always T/O fully manual until I reach 500feet above then I engage AutoPilot.Rgeards, Isagani

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Guest tomahawk_pa38

Hi Isagani,yes - Southampton is quite an interesting take off - I often fly IRL from there to Glasgow, the route as taken from the BA website is as follows:-EGHI dct NorryR41 WCOdct DTYdct SAPCON57 TNTUN57 POLUN601 MARGOLANAK 1A (STAR) for EGPF usually runway 23A nice one hour flight which I can fit in at home comfortably.I tried some of your sugestions last night but I did use flaps 10. I set a 15kt head wind (220/15) and took off on runway 20 (Temperature 10c). Still only just cleared the landing lights and found steering on the ground very tricky with the trim set at 10 (I zig - zagged all over the runway). I'm also still not too happy about pulling back before VR, IRL when I fly my friends PA38 I keep the nose hard on the ground until VR (unless I'm taking off on bumpy grass !) as this improves ground handling.I'm nowhere near max TO weight and I've checked that loads are fairly well balanced front and back, however I will check my joystick settings although I don't have any problems anywhere else. many thanks anyway

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