Need help calculating the basic things.

The airspeed while descending should be of 280 or less like it was said? Combined with the VS calculation that you gave me.

That 280kts is false information.

Seeing that you are really interested, I suggest you get the app Flightradar24. It is a great app and you can watch actual live flights. Remember though, all speeds are based on ground speeds, headings and VS is actual.

If you go to, you can see an actual flights speed, VS, altitude, heading, minute by minute. This is extremely educational if you want to fly like a real world flight.

I need to go to sleep now, but if you are interested I can help you find the information tomorrow night on flightaware if you can’t find it.

But Flightradar24 is a fun app to get started with :) they also have a website if you want to watch and follow planes on a big monitor.

Also, you can click on my profile for more info.

Anyways, hope that helps and talk to you tomorrow perhaps.


I´ll have everything in mind, thanks for the help. Two more questions, at which altitude should I start using the flaps? When do I turn off the auto pilot?

Thanks for everything, I´ll write everything down in a notebook right now.

One more thing, find tutorials and comments by Aernout, he is a real world A380 pilot so you know you are gets the correct information from him.

I can go over your other questions tomorrow night if you still need it.

Thanks for all the help, I will try tomorrow a flight with the info I received.

Approach speeds and flap settings are dependent on a number of varying factors such as type of aircraft, weight, winds, etc.
Modern airliners have computers to calculate speed, flaps, trim, thrust, etc. In IF we don’t have computers, but we have the next best thing, the attitude (pitch) indicator.

Planes are designed to fly level. During your descent and approach you will want to keep your plane level and no more than 2.5 degrees pitch up.

As your plane slows, it will start pitching up. When your plane’s pitch nears 2.5 degrees, you will need to extend the flaps enough to bring the nose of the plane back down to level. As your plane continues to slow you will have to continue to extend flaps each time your nose pitches up to 2.5. Keep doing this until you are at your final flap setting. 737s generally land with flaps 30.

You should be at your final flap setting and approach speed with gears down, between 1,000 - 1500 feet above ground level.

From here you will need to keep your FPV pointed to the start of the runway while maintaining enough speed to keep your attitude/pitch between level and 2 degrees. If your plane starts pitching higher then 2 degrees, you will need to slightly increase your thrust/speed to bring it back down to the horizon.
If your plane starts pitching below the horizon, you will need to decrease your thrust.

A good practice to get into is to set your landing weight for every plane to 25%. And for every 737 approach and landing, use the horizon to make sure your plane is level. These will be your two constants for every approach and landing.
Now you can focus and practice your throttle management and flap control for various approaches and wind conditions.

Here is a screenshot of how your attitude indicator and FPV should look on approach.


@Thomas_Hense… Best of the lot Tom. The Right Stuff! Max

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In clear weather real world 737 pilots will deactivate auto pilot anywhere between 5,000 and 500 feet above the runway. There are no rules, it is entirely up to the pilot.

To eliminate the nose dip/bump you will need to move the default position of the elevators to the position they are in during descent. This is done by adjusting the trim.

For the 737, with 25% weight, flaps 30 and an approach speed of 137kts, set your TRIM to 15%. CALIBRATE, and then de-selected your auto VS.
No more nose dip :)

At 160kts try 14% trim,
180kts try 13% trim.

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I tried to make a flight with the descent rate measured at 1680, from 26000ft to the altitude of the airport (146). I thought I didn´t quite make it and used a descent rate of 2000. I ended up at 2000ft, far from the runway, do I need to follow what I calculated?

As your ground speed slows, you need to adjust your VS (every minute or two). As your ground speed slows your VS will decrease.

And depending where you are between waypoints you will need to level out at times, just like the real aircrafts.

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What type of aircraft are you on for the flight from Portland to Seattle?

All the 737s. The 737-900 is my favourite because of the longer fuselage. Makes it a bit more challenging.

Regarding the autopilot, if I put the Altitude to 0 for the VS to turn 0, and then I turn off the A/P, can I avoid the nose dip?

I am an accuracy nut, I like this the best it is what I fly by. It is intended for the A320 but there are things that you can use to apply to your everyday flying like how to calculate TOD = Top Of Decent. A simple way to calculate it is:

Use 6.5 miles per minute (at Mach .65 in descent) as the basis. If you are cruising at 33,000 ft. and wish to descend to 5,000 ft. at the next waypoint, at a descent rate of 1,800 ft./min., you need to figure the time to descend 28,000 ft. (33,000 - 5,000). Divide 28,000 ft. by 1,800 ft./min. and you will get 15.56 minutes. At 6.5 miles per minute, you need to begin your descent at 101 miles from the next waypoint (15.56 minutes multiplied by 6.5 miles per minute).

That was a simple no wind calculation the link gets in more detail like to idle your throttle, maintain decent at .65 Mach until 16,000 feet and 250 KIAS 16,000 and below.

Happy Flying!

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This post was flagged by the community and is temporarily hidden.

It was with the A318, A319 and A320. He is flying the 737-700.

Only if your speed is fast enough to where your pitch is in line with your FPV which would be around 230kts.

Most of the information contained in that link is wrong. The person who wrote it did not do his/her research very well.

I’ll have to eat my words, wrong one. I actually have a US Airways/American Airbus (that was uploaded to to internet) manual somewhere that I now cannot find the link to…proofread…lesson learned, sorry.