To Follow or Not To Follow The F/D

[Sky_Captain]

Me, I've only started on the 737, and its my first "Big Jet", but I found myself a little lost last week while in the sim of a 737NG. Most of my training has been done on the Cranebank 737-400, and this was my second time in the NG sim.
My problem came about while on a single engine ILS approach. I was given an auto-pilot failure after VOR/LOC and hand flew it from there. When I armed APP and the flight director followed the ILS fine until about 3 or4 miles.
To my lack of knowladge, I was a little unsure of NG power settings for single engine approach (anybody with those figures for a LW of 55tons please let me know) but I did my best to maintain the VREF ICE speed. What happened next totally lost me. I drifted slightly right of the LOC and when the F/D started moving left I followed but never got the dot right in the centre, after that it continued left and even when I was at dead centre with my dot it continued left while the LOC moved right :uhoh:
In the end, this problem cost me big, a partial pass on my OPC :{

I eventually gave up on the flight director and followed the LOC, and yes the right frequency was in and idented and the right course was set on the MCP :ugh:

So what do the experts think? Sim Fault, Bad Flying or just the way the 737NG F/D acts.

Thanks for any replies,

S.C. :ok:

[Rainboe]

Sounds to me in the struggle to hold on to the single engine approach, you might have let your trim go out of line. The flight director only gives correct indications if the aeroplane is trimmed out properly. Watch the position of the control wheel and try and keep it horizontal.
*PS don't worry, we all do it. I did the same on an engine out NDB approach and scored about 2/10 on my own estimation!

[Sky_Captain]

Good Point, I suppose with the constant changing of power and pitch settings I had no way of keeping it trimmed. Worst was that a 20kt cross wind didn't help :ouch:
So that leaves me with a problem, have no idea when I will be re-booked for another OPC, cant afford to travel abroad to practice in a good sim since we dont have one in the green isle, I guess I'll just need to learn pitch power settings for the NG.

Anybody start me off with a rough guide for both single and 2 engine approach?

Many thanks,

S.C. :ok:

[Rainboe]

Flying this self same sim, I found it no help trying to memorise power settings. Just remember that you need a fair chunk more power on S/E and fly the aeroplane!.

[Sky_Captain]

I know what you mean, but my conversion course wasn't the best. When I flew the 400 at BAFT I got pitch/power settings for everything, then got nothing for the NG. Havn't been in a sim or flown in 3 months and was expected to fly perfectly for my OPC:confused:
I suppose since I have to re-do this part again I just want some figures in my head to try so I don't fail :{
How I hate playing the waiting game :mad:

S.C. :ok:

[Updraft]

The Flight Director gave me a lot of grief in my initial Ng time. Sometimes you need to "look thru" the F/D.
Try the following figures as a starting point and fine tune from there.
Prior to G/S slope capture single engine, think 5,6,7,8.
5 degrees flap
6 degrees attitude
78% N1
1/2 dot under slope, gear down, flap 15, maintain 6 degrees (a little forward pressure required)
At G/s capture 2.5/3 degrees attitude and approx 73% N1.

Two engine figures can be extracted from Flight With Unreliable Airspeed tables in QRH.
ie 737/800 24k 60 000 kg
Flap 30 1 degree attitude 58% N1
Flap 40 -.5 degree attitude 64% N1

Use these as a start point and fine tune from there.

Good Luck!

[BOAC]

To add, for the -700 from Boeing QRH:

2-eng
60T F15+10, pitch 3.5, 51% N1
50T """""""""""""""""""""46%

Always been taught to add about ?10%? for OEI (oh to ever settle down at an N1:D ), and, of course, do NOT try to be smart and fly (Vref15+10)+5. Get a little slow and whoops!

.....and.....always look 'through' the F/D when flying the ILS, 2 or 1 engine. I preferred the inverted 'V' F/D myself, as I always felt it was more positive.

Check PMs

[Sky_Captain]

Thanks for the replies everybody, bit nervous about failing my first OPC :ugh: and every bit of advice helps.
Updraft, some nice ballpark figures there for me, I'll definately try them and fine tune as necessary, Thank You :ok:

BOAC, also many thanks for the help. Send you a PM now.

Any other good tips for man-handling the NG out there, then please post them here.

S.C. :ok:

[Rainboe]

I think we all, or almost all, fail checks from time to time- I certainly have and I am not ashamed to admit it- and more than once! I haven't killed anyone yet, and neither have you. You sound as though you are doing it all with minimum experience or great lack of ongoing experience. You just have to put it behind you and thrash away and do your best. You are not going to stumble and drop out having come this far- you've already done 98% of it- just persevere and don't get disheartened. This is what you've set your heart on- just do what needs doing and you will get it.

[Sky_Captain]

Thanks Rainboe, I've given up everything for this and right now i've too many bank managers knocking on my door for me to fumble at the last hurdle. All I need now is a date to redo what I missed in the OPC and a start date for going on line. Wish it was easy to get those!

Its encouragment like that I need, Thank You :D

S.C.

[Truckmasters]

Simple question - depending on how long you have been playing with F/D?
Did your annuciators indicate that the app mode had captured. I have seen guys have the HDG bug on RWY HDG and the F/D has never come out of HDG mode due various issue. Just something to watch

[Sky_Captain]

Yes Truckmaster, APP mode had been selected and was shown in the annunciator. HDG and frequencies were also correct. The examiner on the day believes it was due to the aircrafts drift and momentum, I think he meant it was crabbing to the right of the LOC and even though I turned the nose left it continued to crab. The cross wind was 15kt coming from my right?

So Can the NG easily crab :confused:

S.C. :{

[Rainboe]

You were out of trim. Nothing else! Forget crabbing- that's irrelevant. The Flight Director indications are only correct if you are correctly trimmed.

[Sky_Captain]

My appologies Rainboe, i'm not discrediting your answer, it was just what the examiner said that threw me. Although you are right about the trim, at flap 5 I was trimmed then after gear down flaps 15 I did not touch the trim. Next time i'm in the sim, i'll correct for trim and hopefully things will go my way:)

S.C.

[FlapsOne]

It sounds almost certain that you were out of balance.

The 737 slip indications are punk so the only good way of doing it is to 'kick' (rudder) the control wheel till it sits horizontally.

Correct balance is the absolute key to flying OEI half-way accurately.

You have a tremendous amount in our favour that you have recognised a problem and are taking steps to recover. keep that attitude and you will get there.

I have to say though, I would have been a little disappointed with the attitude of your instructor/examiner if I had left a part failed OPC/LPC without receiving a full and clear explanation of the reasons and causes of the fail.

Did you get another go at that part of the test?

[Rainboe]

Sky-Captain, the way you mentioned trimming was as if you had it trimmed out at Flap 5, selected landing config and trimmed, and left it at that. Every power change, no matter how small on one engine, every speed change, you have to retrim it out. Don't bother with the rudder trim too much, you can't keep taking your head away from the panel. In your scan, keep checking the control wheel. Your feet should be fairly frozen on the pedals- as you increase thrust, push a bit more rudder on, as you decrease, take a bit off, but all the time in your scan, you should check the wheel horizontal. If it starts tipping, move your foot on the lower side of the control wheel. When you start going out of trim like that, the Flight Director is no longer giving you USDA Grade 'A' information!

Forget worrying about crab- that is nothing to do with it. If you are in trim, the FD will sort that out for you.
Remember, trim, trim, trim, then for good measure, trim again. You should walk out of the sim with a trembling leg!

Don't worry- you will walk it next time.

[Sky_Captain]

Rainboe, I promise you know, i'll limp out of that sim if it means passing. I was a little unsure if it is necessary to continually trim the rudder when coming in for landing or just taking it all in your legs and "leg flying it" :ooh:
Also I'll keep a good moving eye on my elevator trim :8

FlapsOne, Thanks for the advice, I never fear asking for help, and always find a lot of good people on this site willing to share their expertise. I can't blame the examiner too much, I was lost as to what had happened and took his explanation to heart. Although, at my low hours experience and this being my first type rating, I felt it a bit tough to be expected to perform perfectly after being made to wait 3 months since my LPC and last bit of flying, for an OPC. I wish I could have afforded some practice time in a sim between those 3 months, but having to travel to the UK and then pay for an NG sim, well right now its beyond my budget. Just sold my car to pay to redo the part of the OPC I failed.

But anyway, enough of my boring story :zzz: I'm just waiting now to find out when that OPC renewal will be.

Thanks again,

S.C. :ok:

[Rainboe]

Get this clear SC. At some stage set up a reasonable rudder trim (about 4 I think it was). Leave the trim alone after that- now your legs take over completely. Lock your heels on the floor, and hold it. Make small movements in line with thrust on final approach, but you will be holding quite a lot of rudder pressure. As you push thrust on, press rudder, and vice versa, frequently checking control wheel for horizontal. When you go around, trim elevator forward, and slowly press on rudder as thrust increases- don't slam the pedal forward- it is a balanced process and it comes on quite slow. Rotate the aeroplane. Think about LNav and AA, then what you want to retract flap to and level off altitude. Watch out for that rudder trim again- big power changes- keep watching that damn wheel.

I managed to kid people I could fly a 737 for many years with that- it works!

[Sky_Captain]

Thanks Rainboe, I greatly appreciate your help :)

S.C. :ok:

[Rainboe]

That's half of it. Next 50% is your morale! You ARE going to go in there and you ARE going to show that despite not nearly having enough practice, you ARE going to produce a creditable performance which may not be the best they've ever seen, but considering your basic lack of practice, it is still going to be damned impressive, and it will be a privilege to sign your licence so you can get out there and get paid to have more practice and really show them what you can do when you are allowed to get some proper training in!

Did you follow all that? Are you going to whap their ass next time?

[Swept wing]

Also what is quite helpful is using the ILS display instead of the Map display during the approach on the ND as it will show you very clearly the track line and the ILS course.
If the deviation bar is centered, all you have to do is keep the track line super imposed over the ILS course bar.
This will allow you you to look 'trough' the FD because you now have the raw data on which the FD makes its command in front of you.
On a NG's with GPS, the track line is generally spot on unlike some -300/400, which use IRS and can have obsolete magnetic variation information.

[Charles Darwin]

Did you turn on the FPV dot (flight path vector)?

[Rainboe]

I don't think the 737 simulator in question has that. I would think at this stage it is more of a complication than worth having.

[Sky_Captain]

Rainboe, your on. Next time i'm in there i'm gonna kick some M:mad: F:mad: Ass :E
I don't plan to fail, and I refuse to fail. Because this is what I do, and what I will be doing for a long time. Flying is what i love, and I refuse to give up because of a few hurdles along the way ;)

Swept wing, have to agree with you, the ILS display is the more useful display, and what I like to use.

Charles D, the FPV dot was briefly described to us in our conversion from the classic and has never been properly shown to us, all my group were told about that, is that it is widely used by Airbus pilots :eek:

Anybody know the rates of an NG sim in the UK, and are there any others than those at GECAT and Alteon?

Thanks everybody,

S.C. :ok:

[Rainboe]

Not sure I agree about the ILS being displayed on the Nav screen. Because of your lack of practice, you want to KISS (Keep It Simple Sucker!). You have a GS and a Localiser displayed on your Primary Flight Display. Why try and scan over to another instrument? I would suggest leaving your Nav display on Nav and giving all your attention (apart from a scan over to EPR and a frequent quick look that the control wheel) to the PFD- it has all you need- ILS, Speed, Attitude, Flt Director, Altitude, Heading. Live in this instrument, print out a picture of it and put it by your bed- know it better than you know your girlfriend's face. Keep everything basic and as simple as possible or you will get swamped that much more easily- hence don't bother with FPV, not that the sim has one I think. I know you can put some very good information on the Nav display as Swept Wing advised, but I think your problem is possibly that you are getting swamped and overloaded with information already hence you are not seeing the aeroplane going out of trim, so I feel you would be better keeping it as simple as your previous types without such bells and whistles. A bit more practice and you would be ready to use them though- it would make all the difference.

Some other opinions on that would be interesting!

[Sky_Captain]

Thanks rainboe, as I said before I greatly appreciate your advice on this issue. And believe me everything will be put to memory and a practicle good use :)

S.C.

[spleener]

S.C., follow rainboe's advice as it's good gen. Been a long time since I flew a 737-300 so no NG experience, but I tend to fly all eng inop approaches with the rudder trim neutral - that way I know where the sucker is. If you keep the slip balanced the FD will give you great info.
Reference thrust settings, as a [rough] general rule thrust = fuel flow, so use the same total fuel flow to get a ballpark thrust setting. Not sure if that is easy to see on the NG:8
Best of luck!

[Rainboe]

Spleener- I used to ask at outer marker for rudder trim to be wound to zero whilst I froze my feet on the pedals to take the strain. The 737 training section persuaded me out of that, and I found it was actually better to leave a low trim setting in during the approach and then don't touch it. Rudder pedal forces can be very high, so no point in making too much work for yourself. After that you just watch the slip indicator (very poor) and the control wheel. As long as you centre the control wheel with rudder gently, the Flight Director will give you good indications. I can't remember the power settings very well.

Don't forget, when you land and come back to idle, you no longer have asymmetric thrust, so there will be unbalanced rudder trim suddenly yawing you into the live engine. Just a nasty little surprise when you think it's all over!

[Sky_Captain]

Guys, thanks for all the advice on single engine approaches for the NG. The company has just contacted me and i'm to re-do what i failed on next week, but this time not in the NG but in a 400 Sim? With plenty more experience in this, I hope it to be uneventful and enjoyable.

Rainboe, I promise, my attitude and approach to this wil be determined and confident. With everyones advice here and a little practice before hand, I should be out on the line soon.

Take care,

S.C. :ok:

[Hudson]

The FD is there as an aid. It is not the be-all and end-all of flying an aeroplane despite what some check pilots/simulator instructors think.

If the FD bewilders you on an ILS or go-around (two or one engine) then ask your instructor if you can fly the go-around complete raw data. Now you can see the body angles that are required crystal clearly.

Once you feel competent at full raw data, then when you use the FD you will be aware of its idiosyncrasy's - and as someone said previously, you can "look behind the FD" and smooth things out. 100% FD use can subtly erode your normal instrument scans.

[LGB]

I had the same troubles, though on another aircraft type. Everything went well in sim, except for some of the last sim sessions, my OEI approaches were like I was flying an ILS for the first time.

Localizer and flight director went like windshield wipers!

For my part, I found what caused my trouble:

1. I wasn't enough after the speed. Being in close to the speed-unstable region, thrust must be managed properly. I didn't (in time), so with an engine out, large thurst changes became necessary.

2. The changing thrust affected the slip/skid, so rudder needed more attention, whilst trying to get the speed back to where it should be.

3. The out of trim condition caused the heading to wander, as well as flying in a crab meant the aircraft went in another direction than heading was pointing - causing flight director readings to be unusable, until becoming in trim again. For me it was the first time with a crosspointer FD - before I was used to the "fly-into" type, so I had flight director needles and LLZ/GS crossing one another ... and instructor would NOT let me fly raw data.

4. By this time, localizer would be all over the place, and soon all the parameters of speed, thrust, localizer, glide slope, heading and maybe more would be out of control, resulting in a slalom ILS.


The solution was simple - it starts at 1. above:

Keep a good eye on the thrust and speed. If you have a speed trend vector, a fast/slow indicator or a three digit mach indicator (I guess not on a 737 NG!), then use them for speed trend. The mach indicators third digit serves as a trend because it is so sensitive, not reading the actual mach but checking whether the speed is going up or down - though I am sure you don't have this one on the NG.

Knowing the approximate power settings for the approach is a great help especially if you are inexperienced - at least it saves you from the large thrust changes.

Have fun at the check ride - smile at the instruments and they will smile back to you ;)

[Rainboe]

I scowl and swear at them- and they do the same back!

[IRRenewal]

Rainboe,

You seem confused about which sim this chap is 'flying'.

Rainboe wrote:
hence don't bother with FPV, not that the sim has one I think.
Yet S_C wrote:
Most of my training has been done on the Cranebank 737-400, and this was my second time in the NG sim.

So, this chap was being tested in a NG sim, not the braincrank -400 sim, although most of his training had been in the -400 sim. Why would this NG sim not have FPV?

Rainboe wrote:
apart from a scan over to EPR and a frequent quick look that the control wheelEPR? In an NG?

Don't forget, when you land and come back to idle, you no longer have asymmetric thrustNot true, ground idle on one engine with the other shut down is still assymmetric thrust.

S_C, you keep on talking about your OPC. Are you sure this wasn't an LST?

OPC - Operator Prof Check
LST - Licence Skill Test (test for initial TR issue)

[Rainboe]

Well he said most of his training was done in a 400 sim which I have used extensively. My suggestion was it didn't have a FPV which shouldn't be used anyway if he flies one with it- it is more of an unnecessary complication than a benefit to an inexperienced pilot. We have FPV on the 747- we do not use them or are trained in their use. Personally, I like it, but it's for advanced flying only. I suggested on page 2
I would think at this stage it is more of a complication than worth having.

EPR. N1. What's the difference? It's still only a power setting, and EPR is what he'd have been using at Cranebank.

When you come back to idle for landing and rollout in a 737, asymmetric thrust is just about negligible. If you imagine any difference, it's more than I ever saw! If you land with approach type rudder trim on, that will give you a surprise when you come back to idle and land, forgetting the trim is there. I was just warning him of a little effect that has sprung up on me. I wasn't trying to go into the academical theory of flying, just a few of the most important pointers for someone in his position flying a simulator I know well.

[BOAC]

EPR is what he'd have been using at Cranebank

April fool? 400 has N1s. EPR on the 737 in BA went out with the 200 - and some other dinosaurs:D :D

[Rainboe]

Did it really?- I'm cracking up! It was 8 years ago yer 'onor!

I have been flying an EPR aeroplane since then. Who cares- it says the same thing? Can I plead previous history in mitigation? Mind you, the 200 was fun- like a Cherokee with jets.

[stator vane]

saw the title of the thread and i apologize ahead of time if someone has said this before in earlier reply. (don't have the time to read them all!)

but learn to use the expanded VOR/ILS picture-(in 3/4/5's and NG's) and move that white track line to where it needs to be.

later sim tests will take away the flight directors at times and you must know how to fly the white track line.

every 737 i have flown needs about 56 +/- with two engines and 70 +/- with one engine once on the glide slope. single engine level flight is about 80 something as well. depends on weight.
numbers available else where on 737 sites and they don't change that much over the different models

and like the other replier said, think of your arm directly connected to your rudder leg when single engine and keep them still once set.

airspeed is our friend!!!!

on the EFIS/NG fly the white bug Vref+15 or a bit more (never slower) when single engine and approaching the glide. you can't fail for having a few extra knots of airspeed and it keeps both ailerons and rudders effective.

get slow and live gets much more difficult. i never aim for the Vref+5 trap!

and don't forget the option of going around early and setting up again.

and sad to say, it does (at times) depend on who the checker was!!