formula's & rules of thumb

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Beacon Final
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formula's & rules of thumb

Post by Beacon Final »

I read SpiltS's post about the ILS formula and thought why not just have a post that is for formulas & rules of thumb.

I am sure lots of green guys like myself (who is about to renew his IFR) and others could benifit from people just throwing a trick or two in two the pot.

I know CAT DRIVER and Ol Timer should have some goodies for us all.

8) Beacon


And maybe post some links to cool websites to.....
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N8
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Rate One Turn Formula

Post by N8 »

If you IAS is in Kts

10% of your IAS + 7 = degress of bank required for a rate one turn



If you IAS is in MPH

10% of your IAS + 5 = degress of bank required for a rate one turn
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Post by ndb »

The later it is, and the drunker you are, the better she looks. Here's a handy rule of thumb: add 1 point for every hour after 10pm, and another point for every 5 beers you've had that evening.

So a woman who starts as a "2" at 10pm, by 3 am has been upgraded to a 2 + 5 hours = "7". And if you've had 15 beers that evening, she now looks like a 7 + (15/5) = 7 + 3 = "10".

Then there's the "1 in 60" rule ... for every 60 women that you walk up to and say, "Wanna f-ck?", 59 will refuse, and 1 will not :lol:
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Post by Red1 »

to maintain the 3 degree standard glideslope on an ILS.
Airspeed /2 = rate of descent required to hold the glideslope
Ex: 140kts/2=70 - 700FPM descent

Also when coming in for an arcing approach, take your airspeed and divide by 100 - this will give you how far back you should start your turn for the arc
Ex: 140kts/100 = 1.4 NM so on a 10 DME arc start your turn at 11.4 DME so as to turn right onto the arc - assuming you use a standard rate of turn
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Post by Cat Driver »

I find that if my thumb doesen't get in the way I can gain a stroke when changing hands.
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Post by SplitS »

Come on Cat, more wisdom and less sarcasm...


Descent Rule:

3 x the altitude to be lost (present alt - Airport elev) = Distance to start your descent in miles

Rate of Decent Rule (3 degree)
Groundspeed /2 * 10 = rate of descent (in feet per minute)
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Post by loopy »

What's wrong Cat? :roll: The Misses still not letting you in the bedroom? whip
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Post by oldtimer »

In a pressurized airplane, descent point is a function of cabin altitude and groundspeed. Keep a 500 ft/min cabin descent rate. depressurize 500 above Airport Elevation. Divide that by cabin altitude to loose will give time the cabin requires to descend. Multiply that by the groundspeed in descent in nm/min. Level off 10 miles before the FAF. FL260, cabin @ 6500ft. descending to sea level a/p. (Cabin depressurize at 500ft.) 6oooft by 500 ft= 12 min @ 330 kts, 5.5 nm/min= 66 miles back but to be down by 10nm back. start down @ 75 miles from the FAF. Loose 24000 ft in 12 min. 2000 ft/min descent. Comfortable numbers for a B350. adjust by wiggle. nobody is perfect. Better yet, let the FMS do the calculating. Just be down by 10 back of the FAF. Monitor the time to waypoint.

Descending from the flight levels, if the altimeter setting is high, set the cabin low. if the altimeter is low set it high. from 29.92 every 00.10 in hg above or below set the cabin 100 ft above or below 500 ft. Airport @ 3500 ft. depressurize @ 4000 ft. Altimeter 29.92, set cabin @ 4000 ft. Altimeter at 29.80, set the cabin @ 4100 ft. Altimeter @ 30.10, set the cabin at 3900 ft. and so on. Better yet, let the co-pilot do it.
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Post by Beacon Final »

Good stuff, thanks boys!!! Is there a website that has rules of thumb on it, I knew of one once, but can't find it with google.

BF :P

PS: ndb I may have to try out the 1 in 60 rule..... :shock:
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Post by Nark »

http://www.flightinfo.com has a section with rules of thumb's on it
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Post by ahramin »

sweet and juicy:

divide by 100 IS 1%.
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Post by loopy »

disregard
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Post by Dockjock »

Jet A (L) fuel order PER SIDE = Total Fuel Req'd (lbs)/10 x 3

ie. you need 1500 lbs of fuel (total). 150 x 3 = order 450 L per side. Works well in a/c with one tank per wing. Add a fudge factor too most times for perfect fuel ordering with no calculator!
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Post by FA28 guy »

Radar seperation If you have space between the targets it's safe.
If the trailing aircraft can read the skin number of the traffic in front give him hell for going to fast.
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Post by Disco Stu »

cpt sweet'njuicy wrote:i must read more carefully :roll:
HA HA DUMBASS! :lol:
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Post by Expatriated »

Here's a couple:

Hydroplaning Tire Speed (rotating)- 9x square root of tire PSI
Hydroplaning Tire Speed (non rotating)- 7.7x square root of tire PSI

Speed of sound- 39x square root of (temp + 273)

Mach Number- TAS divided by speed of sound

TAT calculation- 2x altitude minus 44

SAT calculation- 2x altitude minus 15

Farenheight to Celcius- Divide temp by 2 and subtract 15
ie: 71 F= 71/2 - 15 = 20.5 C
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Post by RB211 »

TOD: 3 x Altitude + about 10 miles for decelerating at the appropriate times.

Or where the 'box' has the 't/d'! :wink:
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Post by oldtimer »

For all new right seater,
"It" my turn to buy"
"Ill take the fat one"
" It's cold and rainy, I"ll do the walk around."
Nuff said.
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The average pilot, despite the somewhat swaggering exterior, is very much capable of such feelings as love, affection, intimacy and caring.
These feelings just don't involve anyone else.
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Post by Beacon Final »

Here is a good American site, its called Aviation Communication. The link below has about 20 rules of thumb. But I think most are already menitioned above.


http://www.flightinfo.com/rulesofthumb.asp


It has other cool sections like, help for instructors, airline addresses and such....

BF 8)
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Post by dewpoint »

(1/minutes to last call at the bar)*thirstyness = IAS
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Post by oldtimer »

It is not a rule of thumb, but rules to live by.

never do anything stupid - quickly
Never fly the A model of anything.
Never fly an airplane with paint on the rudder pedals.
Never run out of airspeed, altitude or ideas all at the same time.
You can only match the record for low flying
Never trust a skinny cook.
Never sas a waitress.
The only time you have too much fuel is when you are on fire.
Navy pilots version of Air Force pilots. "Flair to land, Squat to pee."
That bug splat on the windscreen can turn into a Cessna 150.
Never underestimate the power of gethomeitus.
A thunderstorm is never as bad as it looks - it"s worse.
Nature always sides with the hidden flaw.
In poker, the only thing that beats 4 aces is a Smith and Wesson.
If the good lord had intended man to fly, He'd given him more money.
Forget about power, thrust, lift, drag. What makes an airplane fly is money.
If it floats, flys or giggles in bed, it's probably cheaper to rent.
Interchangable parts won't.
Those who can't - teach. Those who can't teach govern.
A good landing in daylight is like kissing your sister.
A night carrier landing is like having sex and being in a car wreck
There are old pilots, there are bold pilots but there are no old, bold pilots.
The toughest job in corperate aviation is figuring out the shower controls in a layover hotel.
From 45,000 ft, all layover hotels are the same.
Moe to come.
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The average pilot, despite the somewhat swaggering exterior, is very much capable of such feelings as love, affection, intimacy and caring.
These feelings just don't involve anyone else.
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Post by FA28 guy »

Old timer I'm going to borrow your last post it's a good teaching aid.

Fuel consuption rule of thumb.

A piston aircraft burns five gallond of gas for every 100 horse power. I use canadian gallons for a fudge factor.

E.G. 150 Horses = 7.5 gallons
500 horses = 25 gallons
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