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markwood19

Pitch and Power Settings

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Hi, 

Does anyone have any reference information on pitch and power settings for the 747 for circuit work? I've been hunting through the pmdg documentation for the info to assist with my 'base training' but without luck.

 

I'm a big fan of the IXEG 737 and that came with a huge amount of material on pitch and power settings which was a big help.

 

Thanks!

 

 

 

Mark

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I have some info on the RR engines for pattern work that I use in Aerowinx. I tried the same and they were close but may need some adjustment.

 

250t 40t fuel.

 

F20 TO 1.50 epr 12.5 degree on TO

F10 1000 ft 1.40 10 degree F10

Stay at F10 1.22 per 7.5 degree on downwind

 

45 sec past TDZ on downwind with wind correction 1.18 epr Gear down F20 5 degree down

Final Approach 1.15 epr F25 3 degree.

 

These are a 747 training captain values. He posted a video on doing circuits but it is private so I cannot repost.

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Look in the QRH In-flight performance section. The airspeed unreliable tables give pitch and power settings for various configurations and altitudes.

 

Adam Turley

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Thanks @sgreen91 - I'll try these out. It would be great if there was more information on 'flying the aircraft' in the manuals. 

 

Mark

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On final approach:

 

Pitch with Flap 25 will be around 3 degrees (the aeroplane symbol should be sitting just on top of the 2.5 degree line).

 

There is a nice relationship between weight and thrust:

 

- At 230T you will need about 1.13 EPR

- At 250T you will need about 1.15 EPR

- At 270T you will need about 1.17 EPR

 

...see where this is going?

 

Flap 30 pitch will be touch lower (around 2 degrees or so -- aeroplane symbol sitting just below the 2.5 degree line).

 

Thrust will be slightly higher. How much higher? Easy way to remember: 25 to 30 is 5. So...

 

- At 230T you will need 1.13 + 5 = 1.18 EPR

- At 250T you will need 1.15 + 5 = 1.20 EPR

- At 270T you will need 1.17 + 5 = 1.22 EPR

 

...and so on.

 

These numbers should be a pretty good starting point.

 

RR engines -- I don't know about the GEs/PWs.

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Greetings Markwood,

I'll show you how to calculate it yourself for any aircraft as long as you have the data.

 

First, you will need a couple of documents. FAA ILS aircraft relationship document http://www.boeing.com/assets/pdf/commercial/airports/faqs/icaoadmpart4.pdf, or the QRH unreliable airspeed table. Would also be great to have the FCTM for the aircraft in question. There are some things to consider in the first 2 documents I mentioned. 1. The ICAO document has different sections, 2.5 degree glide slope and a 3.0 degree glide slope. It also has different landing flaps and VREF and VREF+5 data. You have to be careful when looking at this document. You want to target desired landing flaps, 3.0 degree slope and VREF+5 data. 2. The unreliable airspeed charts are based on VREF+10. Knowing this info is key to ensuring you are getting the correct pitch on approach. The FCTM is better because it will have the ICAO data and a pitch chart based on approach, speed and touch down at different weights.

 

The documents above will get you the pitch on approach. Key thing to know is that an aircraft's body angle/pitch will change about 1 degree per 5 knots. For example, if the unreliable airspeed chart says, 1 degree pitch at REF+10, you can expect a 2 degree pitch at REF+5. Another caveat is that these are real aircraft numbers, if they don't match, then the developer is off the numbers. Now that you know how to grab pitch, lets look at power.

 

Power will be a little tricky, 1. The engine type will vary  2. This data is difficult to collect unless in the real airplane 3. This is the most inconsistent data in flight sim due to items 1 and 2. The unreliable airspeed will have some power numbers, but as I stated, it's based on REF+10. Power is not as important, just fly the proper speed. But this process will work well for your approach. I'll use my beloved DC10 as an example of how it works.

 

I flew the DC10-30 for some years and this is how I taught new guys. I use a 10% of gross weight for a lot of techniques.

 

PITCH= 4.5ish flaps 35 and 3.0ish for flaps 50 on a 3 degree slope REF+5

POWER= 10% of your gross weight + 23.

 

So if I was 400K pounds, 40+23 is 63% N1 target. Set it and minor adjustments at REF+5.

 

For you, get in the sim and fly the aircraft. Once on approach at REF+5 with landing flaps, let the autopilot fly it. Note the pitch and power required. Take your weight and develop a formula that gives you the power required. This is exactly how we developed the DC10 power settings. The jets I fly now and some in my past used EPR for primary power. We use fuel flow for these jets. In the jets I fly now, we use different fuel flows for different parts of the pattern. Fuel flow is pretty consistent. You just need to get close and adjust for REF+5. It's nice having a specific power to set during different phases.

 

This process will get you on the mark. I do a lot of flight testing for developers and this is the same process I use when doing the approach phase of my checks.

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There's a famous set of training videos on a famous 747 forum that specifically address flying the circuit (pitch, power, datum). The videos were made for that particular sim so I think it's etiquette that I don't link it here. Not hard to find... however :wink:

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