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stickN'rudder007
1st Apr 2006, 18:44
Hello
i did a search in internet to find tables with power settings for the 737-200 for different flight phases but i did not find something usefull .
Does anyone know a link anywere i can use?
Any help will be greately appreciated .

sarah737
1st Apr 2006, 19:35
Verry easy: fuel flow= speed
ie. speed 220 ff 1000kg/eng
speed 250 ff 1250
300 1500
and the GS flaps 30 ff 1500
40 1700

ANOTHER ton?
1st Apr 2006, 20:20
Eh? Aren't power settings expressed as %, N1 or EPR?

ANOTHER ton?
1st Apr 2006, 20:23
Verry easy: fuel flow= speed
ie. speed 220 ff 1000kg/eng
speed 250 ff 1250
300 1500
and the GS flaps 30 ff 1500
40 1700
Also, if spd 250 is ff 1250 and spd 300 is ff 1500, shouldn't spd 220 be ff 1100?

I am properly confused now....am I missing something really obvious here?

stickN'rudder007
1st Apr 2006, 20:58
Sarrah thanks for the reply but pls try to explain it more clearly because i didnt really get the relationship . Moreover even though you can use fuel flows to get some predictable performance , the 737-200 uses EPR settings which they should be more practicle since this is the chosen reference performance setting for the aeroplane

CaptainSandL
1st Apr 2006, 22:24
From the QRH:
http://www.b737.org.uk/pwratt-200.gif

Aren't power settings expressed as %, N1 or EPR?
Actually using FF to set a speed was common practice on the 737-200. I shall let the ex-Sabena guys elaborate further.

S&L

banana head
1st Apr 2006, 23:35
Actually using FF to set a speed was common practice on the 737-200

Not just on the 732, but on a great number of 'classic' turbo-jet aircraft.

Strictly speaking the only true measure of thrust/ power on these aircraft is EPR ( N1 with Turbo Fans as the Fan contributes a large portion of thrust) however as we know EPR is not a static value, ie if you set an exact EPR, then change speed the indicated EPR will change (Dynamic-static pressure). These older aircraft did not have digitally enhanced/ corrected EPR instrumentation!!

In days gone by it was discovered that trainee's tended to spend a large amount of time fixated on the EPR gauges (or worse still the tiny N1% gauges on the 737) in order to set a reference power, with the consequence that their instrument scan broke down.

Provided an engine is functioning correctly a given Thrust lever angle/ position will correspond to a given Fuel Flow, which in turn will give a steady EPR at a given speed & attitude. The end product of all of this was that if you set an accurate pitch and an accurate Fuel Flow the rest (speed/ EPR) will all settle down nicely. Thus setting power using Fuel Flow came about.

It helped of course that the Fuel Flow gauges were reasonable large too!

Not necessary on modern types, and of course not even possible as ECAMs and EICAS's dont display secondary engine information unless a problem exists (or it is selected...)

I should stress that FF was used to set power flying in the circuit/ training area and on approach. Take Off power was of course set reference to EPR (with an N1 cross check after Air Florida 'v' the Potomac).

To back up previous posters I recall the following working very well on the 737-200:

Level, 210kts, Clean, Pitch 6, 1100FF per eng, (2200FF with an eng inop.)
Level, 250kts, Clean, Pitch 4, 1250FF per eng, (2500FF with an eng inop.)
Level, 170Kts, Flap 5, Pitch 7, 1300FF per eng,(2600FF with an eng inop.)
Level, 150Kts, Flap 15, Gear Down, Pitch 7, 1600FF per eng (3000 eng inop).
3 G/S, Vref30+5kts, Flap 30, Gear Down, Pitch 1, 1400FF per eng (or with Flap 15, Vref15+5kts and an eng inop, FF 1700)

Enjoy :)

downwind
2nd Apr 2006, 01:14
Cruise EPR
To set EPR setting for cruise .74 mach
multiply your FL by 2 and 20 to the first 2 digits and use the result as a decimal fraction above 1.0 EPR
Cruise at FL290, 29 X 2 = 58 + 20 = 78 and use it above 1.0 EPR = 1.78 EPR for cruise .74 mach at FL290
EPR's & Pitch Attitudes (approx 46T)
Power Settings (2 eng)
EPR body angle
Flap up 1.3 4

F5 1.35 8

F10 1.4 7

F15 1.2 4.5

F30 1.3 2.5

F40 1.4 0

Power Settings (1 eng)
EPR body angle
Flap up 1.5 7

F5 1.6 7

F10 1.7 8

F15 1.4 5
Every 2000 kgs of fuel burn re-adjust EPRs
Approx N1 for climb out
Use 89% N1 for a approx 2 eng climb out value

stickN'rudder007
2nd Apr 2006, 22:31
DOWNWIND your M 0.74 cruise setting method with EPR works down to +/- M 0.01 !! . Its one of the best tips i've implemented in flying !
Any other good tips when using N1 power settings for later boeings with the CFM engines ?

Jetavia
3rd Apr 2006, 01:08
Some good materiels here http://www.fmcguide.com/catalog/media/profiles.pdf
For level flight, if you use roughly 62% N1 and about 72% with SE and adjust as neccesary you should be good.

downwind
3rd Apr 2006, 01:38
hmm cfm stuff i'm pretty light on that, only flown the -200, and done the efis sim rating but never flown the real thing.

stickN'rudder007
3rd Apr 2006, 08:10
JETAVIA thanks for the link...i d/l the document and i'm already reading......
And DOWNWIND thanks again anyway .
I should also thank CaptainSandL ans bananahead.....i've used their tables and they work quite accurately

Centaurus
3rd Apr 2006, 11:07
Why does the B737-200 performance tables use EPR for setting climb and cruise power yet N1 for turbulence penetration power setting?

stickN'rudder007
3rd Apr 2006, 11:43
Centaurus my guess for that would be , since N1 is an actual measure of Compressor speed , that turbulence penetration power setting would ensure a better avoidance measure of compressor stall ( that is a partial breakdown of airflow within the engine )
Disturbed air (from turbulence ) and rapid advancement / retardation of power levers , results in the intake air not passing over the compressor blades at a designed range of angles which ensure optimum and smooth operation of the engine . The manufacturer would recomment a engine speed that best assures a minimization of this situation should the aeroplane enter turbulance conditions.
Again i would not like to be categorical on why N1 is used instead of EPR , but since EPR is more of a thrust setting , it does not serve as well as a compressor speed setting for this purpose .
More jet type experienced posters may correct me.

stickN'rudder007
3rd Apr 2006, 11:47
Further to the original request for power cruise settings for the 737-200 , is there by any chance an operating/systems manual anywhere online?

downwind
3rd Apr 2006, 13:18
try these
http://www.hawkerpilot.com/page8.html and http://www.b737.org.uk/pilotnotes.htm in the 737-200 section Part 4: ATA 21 - 71.
they give u a good heads up on the -200 systems

downwind
6th Apr 2006, 13:55
B737-200 Rules of Thumb
Cruise EPR
To set EPR setting for cruise .74 mach
multiply your FL by 2 and 20 to the first 2 digits and use the result as a decimal fraction above 1.0 EPR
Cruise at FL290, 29 X 2 = 58 + 20 = 78 and use it above 1.0 EPR = 1.78 EPR for cruise .74 mach at FL290
EPR's & Pitch Attitudes (approx 46T)
Power Settings (2 eng)
EPR body angle
Flap up 1.3 4

F5 1.35 8

F10 1.4 7

F15 1.2 4.5

F30 1.3 2.5

F40 1.4 0

Power Settings (1 eng)
EPR body angle
Flap up 1.5 7

F5 1.6 7

F10 1.7 8

F15 1.4 5
Every 2000 kgs of fuel burn re-adjust EPRs
Approx N1 for climb out
Use 89% N1 for a approx 2 eng climb out value
Climb Speeds
Use 250KIAS until 10,000ft then 280KIAS/M0.74 thereafter.
<48T 280/.70
Up to 49t 290/.70
50t or greater 300/.70
Max Angle: flaps up manoeuvring speed + 50 kts until intercepting .70
Max Rate: flaps up manoeuvring speed (used for obstacle clearance, minimum crossing altitude or to reach an altitude in a minimum distance)
Engine out: flaps up manoeuvring speed and MCT
Descent Speeds
Des at .70 till 280 knots, idle thrust 2000 fpm, down to 10,000ft to 250kts idle thrust 2000 fpm
Des at .70 till 280 knots, idle thrust and speed brake out 3000 fpm, down to 10,000ft to 250kts idle thrust 3000 fpm and speed brake out
Min fuel .70/235/235
Turbulent air .70/280/280
High speed .78/320/280
Icing
TAT gauge indicates 0c to 10c min N1 40%
TAT gauge indicates 0c and below min N1 55%
TAT gauge indicates -6.5c and below in moderate icing N1 70%
Fuel usage 2kgs per minute for engine anti ice
Fuel usage 2kgs per minute for wing anti ice
Fuel cools at 4c per hour in the cruise
Use Flap 10 when taking off in icing conditions below 0c, improved climb performance
When taxying use no reverse thrust on snow, ice or slush surfaces
Never tanker fuel for an overnight stop at a place that has very cold conditions
Adverse weather conditions taxi with flaps up till entering the active runway, then select takeoff flap
After landing in icing conditions do not retract flaps past 15, until maintenance has checked flap area for debris
Holding
3 minutes before reaching the holding pattern start to reduce to holding speed
Holding speed based on flap manoeuvring speed (min fuel consumption)
Above Fl250, use Vref 40 + 100 kts to provide adequate buffet margin
Holding straight ahead burns 5% less fuel than a race track pattern, so ask ask ATC for 40 nm straight legs for holding
If ATC require you to hold at slower then min clean, for flap 1 you will burn 10% more fuel than flap up
Fuel
Burn rates: (approx)
1st hour 2600 kgs per hour
2nd hour 2500 kgs per hour
3rd hour 2400 kgs per hour
4th hour 2300 kgs per hour
Start/taxi out/taxi in, 200 kgs
80-100 kgs per hour for the APU
Fill wing tanks first then centre tank
Every 2 circuits burns approximately 1000 kgs
Tankering fuel = 4% per hour/per ton
Performance
Flap selection RTOW
Flap 25 45,000 kgs
Flap 15 47,000 kgs
Flap 10 49,000 kgs
Flap 5 52,500 kgs
Flap 2 52,204 kgs
Flap 1 52,204 kgs
>15c always perform a bleeds off take off
Lowest VMCG will always be 108 kts
Limit reverse thrust to 1.5 EPR for passenger comfort
Manoeuvring
15 angle of bank with flaps and after takeoff with V2 + 15
30 angle of bank with flaps up
It takes 25 secs and 2 nms to slow down from 280 to 250 kts with out spoilers
Then from 250 kts to flap up manoeuvring speed 35 secs and 3 nms to slow down
(with spoilers reduce times/distances by 50%)
If flap retraction from 1 to up is not started until above 200 kts, it is possible to exceed flap placard speed of 230 kts and damage the LE slats, this can be prevented by using 210-220 kts as flaps up target speed until LE devices are retracted
Enroute
Instantaneous Max continuous thrust 2.28 EPR >11000 ft
Top of descent 3 x alt + 10
Aim for 250kts, 10,000ft by 30nm out
Misc
To get a mach number to a TAS figure
Eg: M.72 x 6= approx 432 kts (approx)
Jet aircraft altitude selection
Eg: destination to alternate 90nms, so fly at 9000 ft
100 nms = 10,000ft
110 nms = 11,000ft
:}

stickN'rudder007
6th Apr 2006, 19:06
Hi downwind
Thanks for all the info !!
The second website prooved very usefull . i'm also gonna check your new notes.
You may wonder why i wonna learn certain things about the 737-200...well i just like an era of aviation in which the pilot him self gave more input to the aeroplane himself ....and i like to experiment with ways to reduce pilot workload by adjusting stuff quicly and accurately. I found a very realistic 737-200 simulator add-on for FS (A very ambitious project to model the aircraft that unfortunately stayed unfinished at certain parts of the overhead panel systems ) Its a really cool add-on if you are into sim flying.
At the same time its a good way to stay current on instrument flying . Some companies use old sims like this to assess prospective new F/Os during a selection process . Why not get 2 birds with one stone ??