April 26, 2007

How To...Fly The Boeing 737 - The Basics

How To...Fly The Boeing 737 - The Basics

By Kris Heslop (21 July 2005)

Assumptions:

Set up your stock MSFS Boeing 737-400 for this tutorial to the specs below and you can fly along as you read!

Weight – 50,000 kg (110,000 lbs)

Airfield – EGKK runway 26L (airfield elevation here is 200 feet pressure alt)

Temperature - 15 Celsius

Pressure - 1013 mb (29.92 hg)

Take Off Phase:

Firstly it's important not to over stress the engines; there is no over-temp protection on the MS model nor on the real aircraft so if you firewall the throttle like you would on the Cessna you will get to 106%N1 and in reality that is more than enough to melt the turbines. In most cases the N1 limit is worked out by the FMC but there isn’t one on the stock MSFS 737 so use some restraint. At the end of this guide is a table we use for the calculation of the N1 according to ambient temperature if you feel brave enough to figure it out (Appendix A). In our example the N1 should be between 93.7 and 94.2% N1 so let's use 94% which is close enough.

Most take offs in the B737 are done at Flap 5 although you can use Flap 1 or Flap 15 if you wish; for this example let's use the norm of Flap 5. In Appendix B you will see a table from which we will get our V speeds just to make it realistic. First of all using the stripy graph. In the top left by going along the top we find 15 Celsius then follow this down to 200 feet. This puts us firmly in the area marked as A. Now go to the large table below and look at the Flap 5 area. Go across and follow the line of figures marked for 50,000 Kg. You will hopefully see the following figures:

V1 = 127

Vr = 129

V2 = 139

Now get yourself to the hold short point and set up your aircraft with Flap 5, set Course and Heading to 261, set speed to the V2 + 15 figure (154 kt) and the Alt initially to 5000. Autobrake should be moved to RTO (Rejected Take Off), F/D and A/THR should be on and the external lights should all be on also.

Read this first before going barrelling down the runway as it WILL happen quickly!



Firstly you will apply take off power; don’t use the TOGA button as this will give you the full 106% and ‘virtually’ melt your engines, so advance the thrust levers to set 94% N1.

 

You will see the airspeed rising rapidly as you accelerate. Passing 127 kt is your point of no return (V1) and at 129 you should pull back on the stick pitching up to about 20 degrees nose up. Once airborne raise the gear. You are aiming to maintain V2+15 = 154 kt to 1000 feet agl, which in this case is about 1200 feet on your altimeter. If you accelerate past 154 simply pitch up more, if you decelerate below 154 then lower the nose--simple as that!



Passing 1000 feet agl (1200 feet on the altimeter) you need to start accelerating and cleaning up. Lower the nose to about 10 degrees in order to allow the aircraft to accelerate and raise the flaps to Flap 1 setting and 210 in the speed window (you need to press the IAS button to get the A/THR to work as I recall in MSFS). Passing 190 kt you should select Flap 0. With luck if the A/THR is working you should settle at 210 kt and be approaching your cleared altitude of 5000 feet. If the autopilot isn’t in yet then feel free to put it in and use it from here on in!

Below is the diagram of roughly what you just did:

The ILS Approach:

The trick here is to get yourself set up early, as soon as ATC starts to give you vectors (or descends you below 10,000 feet) start thinking about the approach set up. To find the frequencies, etc., look on the plate if you have it or open up the map display from the World menu and click on the airport. This will give you all the frequencies you need including the ILS and its inbound course. Also you will want to look at Appendix C and get the VREF speed of 134 kt (assuming 50,000 kg and 30 flap landing)

In this example we’ll use Gatwick 26L again so you will need to set up the Nav 1 radio to 110.9 and the course window to 261.

We will need to start a little way back in order to get the drag out so let's assume you are coming from the south towards the SFD VOR (117.00). As you approach the SFD VOR aim to be at 5000 feet and 210 kt. Once at 210 kt we can start to dirty up (get flaps out, etc.). Set flap 1 and set 190 kt in the speed window. Passing SFD descend to 3000 feet and leave the SFD VOR direct to TIMBA.

As you approach 190 kt select Flap 5 and speed 180 kt. You will keep this configuration until established on the localiser so get comfortable with it. Track to TIMBA, then TIGER and finally TUNBY. This will give you a nice long final to get established. After TUNBY turn left to heading 290 and hit the APR button. This heading should intercept you onto the localiser at about 13 miles

As the localiser comes alive (starts moving to the center) the autopilot should start to turn onto it. The basic MSFS autopilot isn’t that good so expect it to overshoot and come back onto it. You should now start looking at the glideslope indicator, as this will become your cue for the remaining flap and gear, etc.

As the G/S becomes alive (starts moving down from the top) select gear down, flap 15, speed 150. Landing checks to the flaps.

As the G/S reaches one dot above center select flap 25, speed 140.

As you intercept the G/S select flap 30, speed 139 (Vref + 5) complete the landing checks.



The aircraft is now fully configured to land. All you need to do is watch the altimeter and monitor the ILS. Your Decision Height (DH) for this ILS is 375 feet as you are flying a Category C aircraft on a CAT 1 approach (attached is the 26L approach plate as a separate PDF file). Realistically you would want to take the autopilot out at about 500 – 600 feet so you get time to get a feel for the aircraft. As you approach 475 feet you call ‘Approaching minimums’ and at 375 ‘DECISION’ at this point the choice is yours to continue to land or go around!

Landing:

This is the less complex procedure, but equally important to get right. You should already have removed the autopilot and now it is time to remove the A/THR as well. Try not to change the attitude of the aircraft as you remove the autopilot; annoyingly it will fly the approach better than you so leave well alone. As you come down check your speed. Never go below VREF but try to be between VREF and VREF + 5 as you pass the threshold. You are looking to touch down on the fixed distance markers.

The Go Around

This is the more complex option, although it is better than crashing and dying so we shall cover it. The B737-400 is overpowered and as such will go around even from 35 feet and not touch the ground so don’t panic too much about that. The procedure is a little more complex though so we will go through it step by step.

First of all the actual decision to Go Around must be made, there are a variety of reasons such as:

  • ATC tells you to

  • You aren’t happy with the approach

  • You have no visual reference at decision height

  • An aircraft or vehicle enters runway

  • Any reason that makes landing the more dangerous option

The up and down of it, if you hear the words ‘GO AROUND’ your training should kick in and your actions should be second nature. It may be that someone else can see something that you can’t so better to be safe than sorry, the problem can be debated later!

Your actions are pretty straightforward:

  • Apply go around power (not full power or you’ll melt the engines)

  • Pitch up to 15 degrees nose up

  • Call flap 15 (and select it when not multicrew)

  • When you have a positive rate of climb, call gear up

  • Aim for Vref + 25 to 1000 feet above ground level (agl)

  • When at 1000 feet agl pitch to 10 degrees nose up; select flap 5

  • Passing 170 kt select flap 1

  • Passing 190 kt select flap 0

  • Climb to go around altitude following the missed approach procedure

By The Book:

The tutorial you just did is taken from the official Boeing manual. These are the actual profiles we fly on the REAL aircraft and have come directly from the Boeing Flight Training Manual!

The appendices on the next few screens are taken from the real Quick Reference Handbook (QRH) for the B737-300. The speeds should be there or there abouts for the 400 series give or take a knot or two.

Appendix A – Take off N1 settings

Appendix B – Take off speeds (V1,Vr & V2)

Appendix C – Landing Speeds (Vref ) and Flap Manoever speeds

Note fully configured approach should be flown at Vref + 5kt





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2 comments:

Fat Boy said...

Nice article. Good to see a decent explanation of how the 737 works in flight , from a
Boeing 737 cockpit builder

Unknown said...

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