Rules of thumb

[flying jocks]

Does anybody have any useful rules of thumb? For example this is one that I was told the other day:

Whilst flying a normal (assume 3º glide) approach, the last point at which you should put the gear down to achieve stability criteria before touchdown is calculated as so:-

Look at the g/s from your Nav. Display and multiply by 10, then add the runway elevation to give you the answer in feet (QNH). I fly the A319 and incredibly it seems to work.

Example:

Thr. elevation = 1500ft
Groundspeed = 190 Kts

190 X 10 = 1900
plus elevation of 1500 ft = 3400' AMSL.

Below this point the a/c will not slow down quick enough to be stable at 1000 ft AAL.

FJ

[Cardinal]

That seems clever, I'll have to try it.

[PA38-Pilot]

It might work at sea level, but don't try it at any high altitude airport with a light airplane. You won't make it.

[mvsb1863]

Flying Rules

1 - Every takeoff is optional. Every landing is mandatory.

2 - Flying isn't inherently dangerous. It's crashing that's dangerous.

3 - If you push the stick forward, the houses get bigger. If you pull the stick back, they get smaller. If you keep pulling the stick all the way back, they get bigger again, quickly, very quickly.

4 - It's always better to be down here wishing you were up there than up there wishing you were down here.

5 - The only time you have too much fuel is when you're on fire.

6 - The propeller is just a big fan in front of the plane to keep the pilot cool. If it stops, you will see the pilot start sweating.
7 - When in doubt, hold on to your altitude. No one has ever collided with the sky.

8 - A "good" landing is one from which you can walk away. A "great" landing is one after which the airplane can still be used.

9 - Learn from the mistakes of others. You won't live long enough to make all of them yourself.

10 - You know you've landed with the wheels up if it takes full power to taxi to the ramp.

11 - The probability of survival is inversely proportional to the angle of arrival.

12 - In the ongoing battle between objects made of aluminum going hundreds of miles per hour and the ground going zero miles per hour, the ground always wins.

13 - Good judgment comes from experience. Experience usually comes from bad judgment.

14 - It's always a good idea to keep the pointy end going forward as much as possible

15 - Gravity is not just a good idea. It's the law. And it's not subject to appeal.

16 - Keep looking around. There's always something you've missed.

17 - The three most useless things to a pilot are the altitude above you, runway behind you, and a tenth of a second ago. 18 - Never let an aircraft take you somewhere your brain didn't get to five minutes earlier.

19 - Stay out of clouds. The silver lining everybody keeps talking about might be another airplane going in the opposite direction. And mountains hide in clouds.

20 - Always try to keep the number of landings you make equal to the number of take offs you've made.

21 - There are three simple rules for making a smooth landing. Unfortunately no one knows what they are.

22 - You start with a bag full of luck and an empty bag of experience. The trick is to fill the bag of experience before you empty the bag of luck.:rolleyes:

[stilton]

Wherever you go, there you are

[babemagnet]

Nice Rulles of thumb:

5 times your groundspeed is the VS you need on a 3 degrees glideslope example groundspeed is 150 times 5 is 750 feet per minute descent

6 times the altitude you are flying you can receive the atis or a vor example you fly 30,000 feet 6 times 30 is 180 nm you can receive atis or vor (in good conditions no mountains etc etc)

[Max Angle]

5 times your groundspeed is the VS you need on a 3 degrees glideslope example groundspeed is 150 times 5 is 750 feet per minute descent

Same answer, different working. Add a zero to the groundspeed and divide by 2. Much easier.

[Wingswinger]

A quick way to calculate TAS from IAS:

Sea Level TAS = IAS

5,000ft TAS = IAS + 9% (3 squared).

10,000ft TAS = IAS + 16% (4 squared).

15,000ft TAS = IAS + 25% (5 squared).

20,000ft TAS = IAS + 36% (6 squared).

25,000ft TAS = IAS + 49% (7 squared).

30,000ft TAS = IAS + 64% (8 squared).

35,000ft TAS = IAS + 81% (9 squared).

40,000ft TAS = IAS + 100% (10 squared).

e.g. 250 kts IAS at 10,000 ft = 290kts IAS; at 25,000ft = 373kts IAS; at 40,000ft = 500kts IAS.

[Wingswinger]

Crosswind rule:

Sine of the angle - 30 degrees off - 0.5
45 degrees off - 0.7
60 degrees off - 0.9

e.g. A 30 kt wind 30 degrees off the runway track is 15 kts across; 45 degrees off is 21 kts across; 60 degrees off is 27 kts across.

[rubik101]

In 38 years of flying the only rule of thumb I have managed to learn and use is 3 times the height and around 10 miles to slow down from 250 kts.

Other than that, I think that unless you have a 8GB memory stick in your head, you will one day use one of these rules and forget whether it's times 2 or times 4 and is it the square or the square root?

Just learn to fly the aircraft and forget all these so called 'rules'.

[l8starter]

Experience is everything,and there's lots of different experiences out there, but I suspect there are quite a few low hour guys out there who might feel they could benefit from this thread, and maybe others; you're never to old to learn, new information is stimulating, and my aging brain needs all the help it can get etc., etc.(I'm certainly a candidate for that !)

Just out of interest rubik,or anyone else, when ATC have left you high and you're decending with a 'good rate', and they ask you howmany track miles do you require, how do you come up with a (sensible) answer at short notice,because 3 x height may be a little over conservative in those circumstances ?

L8

[kijangnim]

Greeting,
On the Airbus equipped with ISIS stadby instrument, Altitude divided by 3, well just look at your altitude in meters below 10000 ft read the first two digits of the meters, that your distance.....:ok:

[Tight Slot]

On the A330 its more like 4 times the alt + 10 miles or so. It comes down like an empty crisp packet. (Potato chip packet if from the Western parts...) Massive wing with only 170ish tonnes, long way down...:)

[kijangnim]

Greetings
Tight_slot
As you are on the 330,
above 10000 ft you take the 3 first digits of your altitude in meters to which you add the 2 first digits of your FL,
below 10000 you take the 2 first digits of your altitude in meters to which you add 10 :ok:

[matthewgamm]

Any thumb rules for the A320?

[The Real Slim Shady]

Matthew

Yup.

Fly the 737 instead;)

[HiFli]

The best substitute for brains is fuel.

[fantom]

You are all wasting your lives if you don't fly 320/330.

I am thinking of setting up a charity for 73/5/6/ persons who need rules of thumb.

Poor bu**ers.

[Cardinal]

Any thumb rules for the A320?

Put the hockey stick where you wish to be level :) Airmanship at its finest.

[olepilot]

Any thumb rules for the A320?

Never ever turn down the wx radar intensity when you leave the flight deck!

[bArt2]

To calculate the True airspeed:

TAS = 55,1088 times squareroot T times the squareroot of the squareroot of (1+0,00023157 times IAS squared divided by P times (1+(IAS squared/1750200)))-1 :E

Or if that is to complicated, you could approximate it by using: TAS=IAS+2% per 1000'

Bart:oh:

[bluelearjetdriver]

Quite a good one I use for time travel...E=MC^3 (that's right Einstein....cubed!!!)

[plain-plane]

Quick Cross wind
The part of an hour…:ok:
Any thing over 60 deg off the runway: cross wind is the full wind…(a full hour)
45 deg off is ¾ hour: cross wind is ¾ the full wind.
30 deg off is ½ hour: cross wind is ½ the full wind.
20 deg off is 1/3 hour: cross wind is… well i think you get the picture… but still: 1/3 of the full wind.
nornally accurate to within 2 kts… :D

[Leave 5 on the glide]

Tas = Ias + Fl/2

[cjam]

The total amount of cash you'l give your current wife when she leaves in 1000's, is your average cruise TAS /2 .
This only works for wife one and two, after that divide by five.
Makes C172's look attractive.

[Pilot Pete]

When to turn in on a visual approach from aloft downwind:

On a Boeing, be gear down flap15 (737) or 20 (75/767) passing abeam the touchdown threshold, 2 miles out abeam. Start a stopwatch and descend at idle thrust. The timing to extend downwind is;

Height above T/D threshold/100 x 1.5 and if you want to really cream it take off 1/2 the tailwind component in kts.

e.g. Pass abeam at 5000' AGL.

5000/100=50 50 x 1.5 = 75 seconds

This works well when new/training. With experience and if you want to really nail it, say with a 15kt tailwind downwind, take off about 7-8 seconds....it looks quite tight and it is, but you will stabilise on final into a 3 degree descent from above......

Take landing flap as appropriate, usually turning final. If the timing works out less than 45 seconds then make it a normal visual circuit, i.e. level off at 1500' AGL and turn in at 45 seconds (i.e. if you are passing 3000' AGL or less as you pass abeam, you are not really flying a visual approach from 'aloft', merely descending to circuit altitude before turning base/final).

Works a treat, especially at places like Pafos where you are often kept high and pass abeam at something like 8000' AGL.

PP

[Permafrost_ATPL]

Good rule of thumb to keep you out of trouble on takeoff: the relationship between TOW and V2.

On the 737-700, the number of tons of your TOW minus 22 should be pretty close to the last two digits of your calculated V2.

e.g 55 (tons) minus 22 = 33, thus expecting V2 of 133.

Work it out for your own aircraft and fly safe...

P

[TO MEMO]

Good one for the Sim.

both engine flameout and gliding to an airport 2 MN for each 1000 ft. And you`ll have to lower the gear around 2000ft.

Add 2500ft for an 180º turn (down wind to final). 1000ft for a 90º turn

[mnttech]

Take Pounds times 1.5. Drop the last zero and that is the gallon amount.
Need 1000 pounds of fuel?
1000 X 1.5 = 1500
Drop the last Zero = 150 gallons of jet fuel.

[Fark'n'ell]

Hey MBSV1863.
You forget Never take thine altitude in vain lest mother earth rise and smite thee:)

[mcdhu]

My Mum said to me as I went off to join the Air Force over 40 years ago:

''Always fly low and slow and use lots of top rudder in the turns.
Always keep your fingernails clean.
Never ask a lady what has been wrong with her.
Never look in a lady's handbag.''

Not bad advice really - thanks Mum.

Cheers,
mcdhu

[fantom]

I just remembered a really important one:

"A wet owl never flies at night."

Served me well.

[40&80]

Dear Lord..Let not my overconfidence exceed my ability.
Remember..It is the one you do not see that gets you.
Shut mouth catch no fly.
When belly touch back bone pilots talk sense.
Talk is cheap money buy land.
Never hang your basket higher than you can reach.
Check Check double check re check check.
ScanScanScan
Pitch Bank Balance Power.

[capster]

In god we trust, the rest we check.

Always roll towards the sky pointer

[misd-agin]

TO MEMO (http://www.pprune.org/members/176635-to-memo)

Join Date: May 2007
Location: Europe
Posts: 50


Good one for the Sim.

both engine flameout and gliding to an airport 2 MN for each 1000 ft. And you`ll have to lower the gear around 2000ft.

Add 2500ft for an 180º turn (down wind to final). 1000ft for a 90º turn



Actually modern jets have glide ratios around 18:1, which equates to 3 n.m. per 1000' of altitude. 767, designed about 30 yrs ago, is 17.9:1.

TAS divided by sink rate/100 = glide ratio. Eg, 260 KTAS/1300 FPM = 20.0 (or the cheating way, 260/13 = 20)

Hmmm, have to figure out what the 757 winglet glides at.

Manuals provide the best gllide speed (L/D). Check out the "dual engine flameout" driftdown speeds. Typically (last 3 a/c I've flown) it's very close to Vref 30 + 95 kts.