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727 Captain >> 727 Captain >> Flaps & Slats
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Message started by LOU on Mar 23rd, 2010 at 12:53am

Title: Flaps & Slats
Post by LOU on Mar 23rd, 2010 at 12:53am
How about a quick look at Leading Edge Flaps and Slats on the 727 wing.


Here is a look at the underside of the 727 wing
showing all the leading edge slats and flaps extended.
Flaps 5 degrees is selected in the cockpit.
The trailing edge flaps are also at 5 degrees.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If you look at the F/E Aux panel on the P-6 wall to the right of the F/E panel
you will see a check unit for the leading edge flaps & slats.
The panel has a amber in transit light and a green locked extended
light to show the position of the device.


In this photo it shows all the lights being tested.
The lights are a bit washed out in the photo, but the top lights
are the green and the lower are the amber.


As you select flaps 2 degrees the trailing edge flaps move
to the 2 degree position and the critical slats (2, 3, 6 & 7) extend and lock.
The slats are from aircraft left to right 1,2,3,4 - 5,6,7,8
In this front view, slat 1 is to the right as you view the image.


In this photo the flaps are at 2 degrees and the critical slats are extended and locked.


As you select flaps 5 degrees the remaining slats (1,4 - 5 & 8) and the Kruger inboard flaps extend.
The Kruger flaps are flat leading edge devices that rotate out from under the wing and
extend down and somewhat forward of the leading edge. They are at the thick part of the wing root.
The slats slide forward off the leading edge of the wing and are more aerodynamic than the inboard leading edge flaps.
If you look at the 747 wing you will see that the leading edge devices are a type of the Kruger flap in that they rotate out
from under the leading edge as opposed to sliding forward off the leading edge.
The DC-9/MD-80 wing leading edge has all slats.



Here is the test panel showing ALL the leading edge flaps and slats extended.


Each leading device had its own hydraulic actuator and was locked up and down.
There was a check list of failure and faults of both the leading edge and trailing flaps.
There was a speed additive for various devices that did not extend.

All the leading edge devices have the ability to melt ice
as hot engine air is ducted through the wing leading edge
while they are retracted.

Lou








Title: Re: Flaps & Slats
Post by JETPILOT on Mar 23rd, 2010 at 1:27am
This description is excellent but is not complete without talking about the leading edge flap agreement lights up front on the panel.

I had a checkride question I liked to ask that almost nobody ever answered correctly..... If you have lost A system hydraulics and need to extend the flaps you need to use the alt flap extension switches. The abnormal checklist will tell you to put the flap handle in the flap setting you want and then use the switches to extend the flaps/slats. You put the flap handle in flaps 2 position and extend the flaps/slats to 2 on the indicator but you get a LE flap amber disagreement light. What do you do.....

Title: Re: Flaps & Slats
Post by LOU on Mar 23rd, 2010 at 2:41am
Yo JP a trick question  ;D

By putting the flap handle in the flaps 2 degrees position you will get a disagreement (amber) light because you used the Alternate Flap switches on the overhead panel.

1. Open the guard and flip the switch to ON. This arms the two alt flap switches.
2. Place the flap handle to the desired position. If you place the handle to flaps 2 instead of flaps 5, you will get an amber light because when you hit either alt flap switch to extend you are using baffle side of B system fluid to extend ALL the leading edge devices at once. Once they are extended, that's where they stay since they are locked down. It would take A system pressure to unlock them and retract. The trailing edge flaps are extended by electric motors and take a while. Once the leading edge devices are extended, place the flap handle to match the TE flap position as they are extended via the alternate system

Another question could be, how many ways can you get the stand-by pump to run???  ;)

Lou

Title: Re: Flaps & Slats
Post by btscott on Mar 23rd, 2010 at 2:42pm
That is very interesting gents! Sounds like a lot of moving parts and things that can go wrong! I think about JP's icing story in the other thread.

Lou, were you the lead Boeing engineer that worked on the design?  :)

How the heck you guys remember all this is amazing. These are very interesting posts. Hope you continue them!

Bruce

Title: Re: Flaps & Slats
Post by Markoz on Mar 23rd, 2010 at 3:33pm
This information from you former 727 pilots is simply "The Best"!

This kind of information is giving me a real insight into how to fly this plane with as much realism as I can ever hope to do. Keep it coming. I'm all ears!

My admiration for Airline Pilots has increased even more through the stories you all are telling. And also, the things you all have to know to fly them and to keep them flying.

Mark

Title: Re: Flaps & Slats
Post by delta dog on Mar 23rd, 2010 at 6:05pm
It's nice to see that guys like Bruce and Mark have such interest the details.
When flaps are up or in the 2 degree position only the inboard ailerons move and when 5 degrees or more are selected the outboard ailerons also move. This increases roll sensitivity at lower airspeeds. Also when the ailerons are deflected more than 10 degrees on the yoke the flight spoilers will come up on the side which you are turning.
Notice on the top of the yoke there are numbers 0, 10, 20. It's very important to know that you don't have 10 or more degrees input [spoilers up] when you lose an engine on takeoff. Rudder is required to keep straight, not aileron. The spoilers will degrade eng out performance.
The sim is not correct as the outboard ailerons always move.
Hope this helps.
Tom

Title: Re: Flaps & Slats
Post by btscott on Mar 23rd, 2010 at 9:23pm
Truly fascinating reading, gents! I don't know that I will retain a lot of it, but I do enjoy reading these comments and getting the tips. The complexity is mind boggling. Why I am so captivated is a mystery to me. To this day, even after 50 years as a pax, when I go somewhere I walk around from gate to gate looking at the different airplanes and watch them taxi. Especially at the gateways like SFO/LAX/MIA/JFK/ORD etc. When I fly UA I listen to atc from block to block and can not understand a lot of it even though I know what to listen for!

Bruce

Title: Re: Flaps & Slats
Post by LOU on Mar 24th, 2010 at 2:08am
Bruce,
Thought you might like to see a landing in a 727-200 at STL
http://www.youtube.com/watch?v=W_ErZ1nakd0
Not as nice as your video, but you can see how much busy work there is in the cockpit.
Note the noise from the main stab trim wheel when he trims.
You will also hear some of the call outs during the approach.
Lou

Title: Re: Flaps & Slats
Post by btscott on Mar 24th, 2010 at 4:10am
Lou -

Magic! Pure magic! That can't be by design! Total mystery! Thanks.

I worked for Frontier Horizon here in DEN for the only year of their existence ----1984. I got to know most of the flite crews and, as a result, I got to ride the jump seat about a dozen times. We had 7 722s and our rtes were DEN to SFO/ORD/LGA/IAD/TPA/MCO. It was a blast. Had no clue what went on up there at the time. Wish I could do it again!

I started a flt today IFR JFK to STL (TWA) and botched it because I was thinking about the video and responding to atc instructions instead of paying attention to business. I was at probably 6-7000 ft over Manhattan when I realized I still had flaps 5! I was so disgusted I quit the flight (because I couldn't use the replay for video) and shut down for the day. I'll refly it tomorrow. We're getting a foot of snow tonight so I'll have the whole day. I have trouble multi-tasking! I'll never be able to do it by the numbers as JP says it's done!!  :-[

Bruce


Title: Re: Flaps & Slats
Post by JETPILOT on Mar 24th, 2010 at 8:41am
That's an easy one Lou.... That would be the "Stby Rudder Switch" or the "Alternate Flap Master Switch" and it uses the fluid in the "Baby B" res. It powers the lower rudder and bypasses system A fluid and hydraulicly extends the Leading edge flaps/slats. Alternate Flap Master uses elecrric motors to extend the flaps.

If you lose A and B hydraulic systesm you lose the upper rudder but still have manual reversion on all the other flight surfaces. Spoilers will be inoperative. The engineer has to get out the gear extension handle Push his seat in get on his hands and knees and crank. 2 turns clockwise to unlock the door uplocks and then clockwise til you get a green light. If I remember correctly.

Remember guys. This is a 3 crew airplane and it takes everyone working as a team to fly this plane. The non flying pilot handles the radios and sets up the approach and some of the checklists. The engineer takes care of the systems, performance and some of the checklists as well and monitors the approach so the two guys up frotn don't kill him.

I started as FE on the DC8 with 300 hrs total time and was upgraded to FO with 230 hrs in the 8. The engineer seat really helped me get to the right seat.  Icouldn;t have gone directly into the right seat and been succesful. It would have been too much for me to handle.

I teach in the simulator and have seen guys with 3000 hours as a flight instructor fail the sim portion. You get 4 hours in the sim before your checkride. 1.5 hours into his training he broke down in the sim and just gave up. He couldn't get used to the pace of things and how much faster they happen in a 727 than a Piper Seminole. I tried to talk him back into the sim, but he said he couldn't and he went back to flight instructuing. Not everyone makes the cut.

There are guys who are  great pilots at 500 hours and some FO's with 4000hrs that will never be upgraded to captain becasue they don't have what it takes. Pilots talk to each other the yask around if they have never flown with you before. Everyone has their favorite crew pairings. Some people work better together than others.

It's not an easy job.

Title: Re: Flaps & Slats
Post by btscott on Mar 24th, 2010 at 1:09pm
JP -

I saved your review of this plane (at least I think it's your review)

http://airlinersim.blogspot.com/2009/03/captain-sim-727-captain.html

You said something to the effect that those who actually want to fly the plane by the book won't like it, but that it was fine for those who just want to make videos. I, no doubt, am in the later category! No way I'll learn all this (I don't even buy green bananas anymore), but following these pop quizzes is really fun and interesting as heck!! It's always a pleasure to watch real pros at work ---especially when they are probing each others depth of knowledge!

Gotta go now-----have a video to make!  ;D

Bruce


Title: Re: Flaps & Slats
Post by JETPILOT on Mar 25th, 2010 at 12:36am
To put things in perspective it takes about 3 or 4 weeks of class to learn systems. It takes about 3 or 4 hours of studying each day after class is over. It takes many hours in a cockpit procedure trainer learning checklists and panel flows, then 4 hours in the sim to put it all together. 1-2 hour checkride in the sim with a 2-3 hour oral exam. 1 hour LOFT (Line Oriented Fligth Training) in the sim. 3 TO and landings in the aircraft with a checkairman. Then they release you for IOE (Initial Operating Experience) for 25 hours of flying the line with a checkairman. Then after all that is satisfactorly completed you can go fly the line as a biddding crewmember. And then it takes about 4mo of flying to really get comfortable with the plane. Then for captains every 6mo an FO's every year you go back to the sim for another checkride.

To miss all that training and expect to be able to fly the plane profficiently won't happen. My last company had a 2 week sched. We were on fro 2 weeks and off for 2 weeks and even after being off for two weeks it took one or two fligths to get back into the rythm.

I have a TOLD card and some performance charts I could send you that willmake the flying easier.

Title: Re: Flaps & Slats
Post by btscott on Mar 25th, 2010 at 3:34am
JP & Lou  -

Had a terrible day today with this thing!! Leaving JFK @146k lbs I had to nurse it up to FL320. Step climbed very slowly the entire way with full throttle. Above 18000 I could barely keep it over 160KIAS during climb at about 2000 fpm with fluctuations all the way. Took forever. Once level at fl320 it crawled up to 300KIAS and mach .80. Smooth sailing to STL. No problem intercepting the localizer at 2300ft (used the GPS automated approach). Was at 140kias, flaps 30 and 135k lbs. Lined up perfectly with 30L. Things were looking good. GS kicked in and down I went. -- 2 white & 2 red! At about 1000 ft and 125kias things went haywire---again. It quit descending--had to disengaged AP again. As I hand flew to runway it started drifting left again. Seemed like a crosswind, although I had the wind turned off in FSX. This time I went around. Hand flew the entire way at about 3000ft watching the GPS. Finally got it on the ground, but again drifted left. When I got down I noticed that I had flaps 40. Lou advised against that setting, but I was looking good most of the way. Granted I just try to control the airspeed and visually try to keep the *PAPI happy*, but I think there is something programed into FSX or this airplane that makes a normal visual landing darn near impossible!  :)

Appreciate the offer of the TOLD card and charts, but I am already in WAY over my head here, and I mean WAY over!

Bruce

Title: Re: Flaps & Slats
Post by Markoz on Mar 25th, 2010 at 7:41am
Hi Bruce.

It's interesting that you are struggling to climb. I would say you had your climb is far too steep! Using the A/P I usually start at around 15 degrees on initial climb the lower it to 10 degrees soon after, and I don't have any trouble climbing to FL290 @ 270 KIAS, but to continue on to FL320 I have to climb at around 27 KIAS and 500 FPM. I think the trick is too lower the nose and gain about 300 KIAS above 10,000 feet so the climb is less of a strain on the plane. Easier said than done in my case!

Don't worry too much though. I have a LOT to learn too.

Keep at it though. It sure is fun even though it can be frustrating if all hell breaks loose!

Mark

Title: Re: Flaps & Slats
Post by JETPILOT on Mar 25th, 2010 at 11:48am
The only issue with landing at flaps 40 is noise abatment. It takes a lot of power to overcome the drag of flaps 40 and that power makes alot of noise. Planes with the Raisbeck Quiet Wing stage III modification had the flap 40 detent blocked off and a placard on the panel. You could enter flaps 40 detent if you raised the guard. Raisbeck also reconfigured the flap settings to optimize lift/drag ratio. Interestingly Raibeck did not touch the engines to meet stage III. It did lower the maximum gorss takeoff weight however and used lower EPR settings.

The TOLD card may make it easier since you know your minimum flap manouvering speeds and your approach speeds. You have to know those. Configure the card once and then always fly at the same weight.

You sure yo uhad all the engines running?  :)

The EPR indications aree so screwed up on this simulation. Normal TO EPR at SL at 59 farenheit is about 2.12 EPR and that's firewall power. This plane at firewall power only puts out about 1.93 EPR. The performance modelling concerning power is off as well. The 727 was not a powerful plane, but it is more powerfu lthan CS modelled it. AT MGTOW I used up about 11,000 feet of runway at 13R at JFK. That's not realistic.

Title: Re: Flaps & Slats
Post by LOU on Mar 25th, 2010 at 1:37pm
JP is right - the EPR is low in the model.

Bruce, try this... after takeoff and clean-up of the flaps, turn on the autopilot and control the pitch with the turn & pitch knob. Adjust you view so you can see the trim wheel (zoom out) and out the window. Make small pitch down inputs to the autopilot and you will see small movements to the trim wheel. Out of 10,000 pitch over to climb out at 280 to 300 KTS. Remember, the 727 was called "The Pig" by pilots because it was slow in the climb. The 757 climbs better on one engine than the 727 did with ALL engines running!

I'm not sure what is happening to you during the last part of the autopilot approach. I have tried several autopilot approaches both in G/S Auto and in G/S Manual. Most times it does OK. The key seems to be, as in the real thing, don't rush the approach, get on speed and stay there by small power changes. Flaps 30 or 40 should not make a difference, just more thrust with flaps 40. Every time you change power the speed changes then the pitch changes and the autopilot gets behind and starts chasing the pitch, and there goes the approach.

Remember, what JP said in an earlier post. The airline school was 4 months long, then the sim, then oral, etc. And we were already pilots. You guys do a great job with your flying, and you learn more each time you fly or discuss problems with others. Keep it up!

Lou

Title: Re: Flaps & Slats
Post by btscott on Mar 25th, 2010 at 4:45pm
Gents -

Where to start? I usually turn on the AP soon after gear & flaps up. At about 3000ft I turn off the HDG Hold and turn on VOR/LOC and switch from NAV to GPS. Now the AP is flying the GPS flt pln and I can concentrate on just power and climb rate. I have the elevator trim programed to the left yoke switch below the Hat Switch (Saitek yoke). I try to keep it trimmed at about 2000-2200 fpm on the VSI. Up to about 15-18000 there is plenty of power (I don't know anything about epr and fuel flow etc). But from there on the throttles are firewalled and I have to keep leveling off for a few minutes to let the power get back up over 200kts. If I'm IFR ATC is constantly on my butt to expedite my climb, so I switch channels! Now I'm VFR. It takes forever to get to fl320! Once there and I get back up to 300kts (.8 Mach) all is well.

No problem with the AP on GS Auto picking up the coupled approach. Localizer activates and so does the glide slope. I try to keep the airspeed properly set according to weight and flap settings using small inputs as you say, but at approximately 1000-800 ft agl the nose comes up (even if power setting is correct at about 125kts-135k lbs & flaps 30) and I have to disengage the AP and push the nose down , add some power and then the dance begins! Seems at first I'm in good shape aligned with the runway and I get to 2 red & 2 white. Then the darn runway starts moving around It really seems that there is some sort of programming twist that keeps me from getting back to perfect alignment with the center line. I usually get it on the ground but left of the center line. People yelling and screaming in the back end!! They make me nervous---I think I'll buy the freighter!!  :-[

JP - I don't know what a TOLD card is or how to use it, but if you think that will help I take one!! Is that something you clip on the yoke clip board?

Here's a short video of the landing in STL after I aborted the first attempt and hand flew from there on. I didn't save the flt this time so I'll fly an ATL/STL flight today and try it again. This time I'll save it just prior to intercepting the localizer for 30L.

http://www.youtube.com/watch?v=ZrbrcX02_BQ

Bruce





Title: Re: Flaps & Slats
Post by LOU on Mar 25th, 2010 at 7:05pm
Where to start? I usually turn on the AP soon after gear & flaps up. At about 3000ft I turn off the HDG Hold and turn on VOR/LOC and switch from NAV to GPS. Now the AP is flying the GPS flt pln and I can concentrate on just power and climb rate. I have the elevator trim programed to the left yoke switch below the Hat Switch (Saitek yoke). I try to keep it trimmed at about 2000-2200 fpm on the VSI. Up to about 15-18000 there is plenty of power (I don't know anything about epr and fuel flow etc). But from there on the throttles are firewalled and I have to keep leveling off for a few minutes to let the power get back up over 200kts. If I'm IFR ATC is constantly on my butt to expedite my climb, so I switch channels! Now I'm VFR. It takes forever to get to fl320! Once there and I get back up to 300kts (.8 Mach) all is well.

Bruce,
What T/O weight?
I takeoff at 135,000 to 140,000 # - remember what LP said about needing 11,000' of runway at JFK - these engines are not producing full power at takeoff, so I guess they are low during climb. At the lower weight it seems to climb alright for me. Figure 10,000# of fuel per hour - plus some reserve. LGA to STL is under two hours, so I use 30,000# with no alternate.

In your climb through the teens, don't get slow. Climb at 280 to 300 KTS. You'll just have to accept the pig in climb. The engines produce more thrust as you go faster.

Above FL 180 you need to be IFR in positive control airspace.


No problem with the AP on GS Auto picking up the coupled approach. Localizer activates and so does the glide slope. I try to keep the airspeed properly set according to weight and flap settings using small inputs as you say, but at approximately 1000-800 ft agl the nose comes up (even if power setting is correct at about 125kts-135k lbs & flaps 30) and I have to disengage the AP and push the nose down , add some power and then the dance begins! Seems at first I'm in good shape aligned with the runway and I get to 2 red & 2 white. Then the darn runway starts moving around It really seems that there is some sort of programming twist that keeps me from getting back to perfect alignment with the center line. I usually get it on the ground but left of the center line. People yelling and screaming in the back end!! They make me nervous---I think I'll buy the freighter!!

Let 'em scream! They bought a ticket, give 'em a ride !  ;D

I looked at the video, did you have 40 degrees of flap???
It looked like a lot of flap.

I saw the pitch up around 700', but you did a good job of keeping it on visual glide slope. I noticed the G/S flag so I guess you were on STL VOR using it for DME.

You looked real good to around 50 feet when you let the left wing drop a few degrees. That's all it takes to start a drift to the left and that's what got you over to the left side I think.

You can't slip the 727 very much since the leading edge flaps and trailing edge flaps will scrape the runway with about 5 degrees bank and a firm touchdown. You crab the 727 to landing and just keep the wings level as you feed in rudder to align the aircraft to the runway. In a strong crosswind the procedure is:
1. CRAB
2. FLARE - usually add power as well at this point.
3. ALIGN

In the 757 you can slip it like a Cub since the wings are way up off the ground and the engines also clear with plenty to spare. The autopilot in autoland slips to a landing and does such a good job it makes you sick because it can fly better than you!!!

Title: Re: Flaps & Slats
Post by btscott on Mar 25th, 2010 at 10:06pm
Lou-

I believe TO weight was 146k. I can see that I need to lighten the load a bit.

"Let 'em scream! They bought a ticket, give 'em a ride!" Now that is really funny!!! My wife came and asked what I was laughing at!

The NAV1 radio was tuned to the 30L ILS frequency. I just disengaged the AP and left everything as it was. And yes I was at flaps 40, which I didn't think I was---till I got on the ground.

Awhile ago I set up and ATL/STL flt. I set the fuel with full wing tanks and the center tank at empty. Total weight was right at 150k. While holding short at the active I noticed engine 2 was not running!! CTRL-E would not start it. I reset the flt with 10,000lbs in all 3 tanks and then all engines were running. I still had to nurse it from the mid teens up to fl320, but not near as tedious as yesterday. I think JP hit on the problem when he asked if all the engines were running! I think not!! I think I flew the whole trip on 2 engines including the go around.

Right now I'm paused at fl320 and 295kts. I'm 170 miles from STL and my weight is 139k and I've got 22,800 lbs of gas left. I also cleared all AI traffic out so it's just atc and me the rest of the way. When I resume I will file IFR and get clearance. Then I'll start sweating again! I think I had better buy everyone in the back a couple drinks on TWA?  ;D

Ooops, I just re-read about being IFR above 180!

Crab-Flare-Align. I'll remember that!! Thanks again for all the good advice and help!

Bruce


Title: Re: Flaps & Slats
Post by JETPILOT on Mar 25th, 2010 at 10:38pm
Standard configuration for fuel feeding is tank to engine. Tank #1/3 should never contain more fuel than tank #2.
Sometimes tanks # 1/3 are full and you need to carry more fuel in tank #2. TO is always tank to engine. Then on the climb you should set up the crossfeed operation for tank #2 to supply fuel to all engines until the fuel quantity is equal in all 3 tanks then stop the crossfeed operation and resume tank to engine feed.

For the engineer to start a crossfeed...
1. Inform the captain you are begining a crossfeed
2. Continuous ignition ON
3. All crossfeeds valves open
4. Confirm blue Valve In Transit lights illuminate then extinguish
5. Boost pumps off in tank #1
6. Boost pump low pressue lights illuminated
6. Observe #1 fuel flow guage and monitor EPR for normal engine ops
7. Boost pumps off in than #3
8. Boost pump low pressure lights illuminated
9. Observe #3 fuel flow guage and monitor EPR for normal engine ops
10. Add fuel burn (lbs per hour) on the 3 fuel flow gauges
11. Calculate how long it will take to burn of desired fuel and note time to stop crossfeeed


Title: Re: Flaps & Slats
Post by Markoz on Mar 26th, 2010 at 12:20am

btscott wrote on Mar 25th, 2010 at 4:45pm:
I have the elevator trim programed to the left yoke switch below the Hat Switch (Saitek yoke).

Hi Bruce.

I have the elevator trim set to two of the buttons on my Logitech Extreme 3D Pro joystick (I know. It's a cheapie!). The thing that I find is that once the A/P AIL and ELEV switches are turned on, I can't control the pitch with my assigned buttons on my joystick, the A/P overrides my changes. Could this be the reason the plane is struggling to climb? I have to use the trim UP and DOWN buttons on the A/P to get the changes I need. I always use the 2D A/P panel because even if I look around the cockpit, it is always in view (@ Lou & JP - I know it's cheating). Another thing is, if I undock it, it goes to every camera view I switch to.

Mark

EDIT: I just thought that maybe you DON'T turn on the A/P ELEV switch, which might allow you to use the programmed buttons on your yoke.

Title: Re: Flaps & Slats
Post by JETPILOT on Mar 26th, 2010 at 1:14am
You don't fly a plane with trim. The trim should not be used when the autopilot is on. The SP-50 Block IV autopilot has it's own trim system and independant drive motor. If you want to bring the nose up then you need to use the pitch contro lon the autopilot panel.

As Lou already mentioned you should climb with refrence to airspeed not FPM. 280-310 kts is usually used as climb speed. If you can't maintain at least a 500' per min climb rate you have to notify ATC of this.

Title: Re: Flaps & Slats
Post by LOU on Mar 26th, 2010 at 2:21am
Quick review of fuel use in the 727

During fueling, the three tanks are filled EQUALLY until the wings shutoff (full). The rest of the fuel is placed in the #2 tank.

If the center tank quantity is greater than tanks 1 & 2 :

1. Start ALL engines tank-to-engine. (center x-feed valve open to keep fuel pressure in the cross feed manifold - 1 & 3 x-feed closed)
2. After takeoff, and before 3,000# are burned, start a X-feed feeding ALL engines from tank 2.
  (see JP's F/E checklist - nothing is done with out crew coordination - EVER!)
3. When tanks are equal, return to tank-to-engine.

I talked about this in another post. Two things to remember about the fuel system.

1. Swept wing - wing tank fuel is aft of center tank so the above fuel use is for balance.
2. Center -big tank! Center fuel tank must be equal or greater than wing tanks for structural reasons.
   Bruce, think of the mass of the fuel in the center tank pushing out while the wing tanks are pushing in.
   In your case with wings full and center empty the structure would fail.
   NOTE: CS-727 fuel seems to have an error in that if a tank goes dry, even though the cross feeds are opened
   and the boost pumps are on in the supply tank, the engine quits. Not so in the real plane. In fact, the
   engines - in most cases - will suction feed without the boost pumps as long as the cross feed is opened.

   Do not attempt this at home!  :D
   
   During flight test, we would go through all sorts of weird checks (no screamers on board) and it always amazed me how well this post
   WW II plane did. Remember the CS-727 is a game and not always exact, but it is still - for the money - a very cool simulator.

Also, NEVER use ELECTRIC trim input with the autopilot engaged. To do so in the real plane would trip off the autopilot.
You could use manual trim, but why? The autopilot will do a good job if you have the plane trimmed before you engage it.
Most of the 727 were bent and needed some rudder or aileron trim - that's OK since it is manual.

I just flew a few ILS approaches using the autopilot. I left the autopilot engaged to about 50 feet and for the most part it did a good job. I even had the plane out of trim to see what it would do and after a few oscillations it settled down and flew the approach. The flight director, as far as I can, tell does nothing much but follow the horizon.

Bruce, your videos are great! Keep it up.

Lou
   

Title: Re: Flaps & Slats
Post by btscott on Mar 26th, 2010 at 2:47am
Mark/JP/Lou  -  

Well! You may have exposed a flaw in my systems management. I use trim up/down the entire way with the AP on. There is no VSI Hold. Huh! Now what? I will re-read all this tomorrow and re-assess in the sober light of day (cocktails and dinner just concluded here)! Hmm. Earlier, Lou mentioned using the *Turn & Pitch Knob*--maybe that's my problem!? Have not done that yet.

Well, it's too late for serious business, so I'll just kick back and listen to some of my favorite music! Take a listen:

http://www.youtube.com/watch?v=_4TRSYhrEJE&NR=1

I'll catch up tomorrow!

Bruce

Title: Re: Flaps & Slats
Post by JETPILOT on Mar 26th, 2010 at 3:15am
The 727 is bare bones flying. When pilots were pilots.  ;D

Use the pitch control on the autopilot to hold 280-310 kts. Rememebr the 250 kt speed limit below 10,000 feet MSL (mean sea level). Keep the airspeed below 250 kts below 10,000 then pitch the nose over at 10,000 MSL and accelerate to your climb speed. All but ignore the VSI. As long as it's over 500' per min your OK.

Title: Re: Flaps & Slats
Post by btscott on Mar 26th, 2010 at 4:06am
But, them pilots was trained pilots too!

Yup, I'm schooled on the 250kt limit up to 10,000 with landing lights off above etc.

In the more modern default and freeware planes there is a VSI hold so all you have to do is pay attention to the speed. In this guy I have been struggling with the VSI (electrically?) (AP on) with the throttles mostly firewalled over fl180. I'll try it with just the throttles and no electric trimming, just the manual turn and pitch knob. Have no clue how that works though.

Lou, if I can get down to 50ft on the glide slope with the AP on I would be quite happy. That tells me CS has it pretty much correct. I will work to achieve that goal.

Why did they make this so hard? (must have been the pilots union)  :D

Title: Re: Flaps & Slats
Post by JETPILOT on Mar 26th, 2010 at 4:22am
Hey.... if it was easy everyone would be doing it!  :)

Title: Re: Flaps & Slats
Post by Matt2218 on Mar 31st, 2010 at 10:59am

JETPILOT wrote on Mar 25th, 2010 at 11:48am:
The only issue with landing at flaps 40 is noise abatment. It takes a lot of power to overcome the drag of flaps 40 and that power makes alot of noise. Planes with the Raisbeck Quiet Wing stage III modification had the flap 40 detent blocked off and a placard on the panel. You could enter flaps 40 detent if you raised the guard. Raisbeck also reconfigured the flap settings to optimize lift/drag ratio. Interestingly Raibeck did not touch the engines to meet stage III. It did lower the maximum gorss takeoff weight however and used lower EPR settings.

The TOLD card may make it easier since you know your minimum flap manouvering speeds and your approach speeds. You have to know those. Configure the card once and then always fly at the same weight.

You sure yo uhad all the engines running?  :)

The EPR indications aree so screwed up on this simulation. Normal TO EPR at SL at 59 farenheit is about 2.12 EPR and that's firewall power. This plane at firewall power only puts out about 1.93 EPR. The performance modelling concerning power is off as well. The 727 was not a powerful plane, but it is more powerfu lthan CS modelled it. AT MGTOW I used up about 11,000 feet of runway at 13R at JFK. That's not realistic.


JETPILOT -

One thing I noticed in the 727 config files was that the 'static thrust' was listed as the same for both the 727-100s and 727-200s.  I increased the value for the 722s to a higher figure I found online (forget what it was, something >17K lbs thrust as opposed to ~15.5K) and takeoff performance seemed to improve.

I've been exploring the propliners lately so I haven't explored it much.

Title: Re: Flaps & Slats
Post by nyr81 on Apr 5th, 2010 at 9:16pm
I had no idea about not exhausting the center tank, I am used to operating the 737 and 747 in the sim. So I will fill up all 3 tanks equally and let them feed their respective engines.

Title: Re: Flaps & Slats
Post by JETPILOT on Apr 5th, 2010 at 10:21pm
Thanks Matt.

Tank to engine is correct unless you need to carry more fuel in tank # 2.

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