Simviation Forums

Hi all, I am still having some probs with calculating speed and decent, and was asking if someone could give me the correct instructions.

(1)      Ok, I am flying a 747-400 at 32.000 ft  so what is the cruising speed I should have set for this aircraft ?

(2) I am 100 Nm from my destination airport, what level should I decend to, and what speed shouls I slow down to ?


(3) I am now 50nms from Destination airport, what level and speed should I be at now?

(4) I am now 10nm from destination and visual, what speed and level should I be at now, as to make a perfect landing on the runway?

Thanks again for any help with this.

Tomcat61

This is how I'd do it:
1) M0.82-M0.84 at FL320
2) FL320 divided by 3 = start descent at 107 miles
3) Multiply groundspeed (given on the map GPS display) by 5 to give descent rate in feet per minute
4) As you slow down, multiply the lower groundspeed by 5 to reduce your descent rate as you descend.
5) You should be at around 6-800 feet per minute at approach speeds.

At 50 NM, you'll be around 15-16,000 feet at around M0.5. At 10 NM, you'll be on the glideslope at around 3-4000 feet at approach speed of 150-160 knots.

Hope this helps.  :)

I do it this way...

At FL320 cruising M.84 and 107nm from destination I begin my descent, just as microlight said. Divide flight level by 3=107nm. If I'm not using an arrival or approach chart, I'll just plan on leveling off at 5000ft unless terrain does not allow.

I don't use any formulas for the descent rate, I just shoot for 2000-3000 fpm until I reach 10,000. In the mid FL200s I will maintain 300-315 knots. At 18,000 make sure to get current altimeter settings. At 10,000 reduce speed to 250 knots (may have to use spoilers if your throttles are idle and still too fast), go to 1200-1800 fpm rate of descent.

At 30-50 nm from destination get ATIS and find out which runway, then fly headings that will get you lined up. Maintain 5000ft AGL at your discretion and extend flaps 5 and 220 knots. Should be at 2000ft AGL by the time you are 10nm out (assuming no mountains).

I've got a very handy gauge that works it out for you

Hey Tipster, how do you end up with so many cool gauges!?

Hey Tipster, how do you end up with so many cool gauges!?

LOL - I download any panel that looks like it might have something new - take the gauges and (generally) bin the panel.

I've also collected anything useful from the rare, but occasional gauge links you find on some sites.

I've been doing it for years - around 3,500 gauges in my collection.