How to Set True Air Speed in your Aircraft

Here's how to determine true airspeed with a traditional round dial set up like in many Cessna 172s. You need to know outside air temp, pressure altitude, and indicated airspeed.

[@flightinsight9111]

Check out Private Pilot Online Ground School at www.flight-insight.com/private-pilot-ground-school

[@davidpimentel4400]

😅

[@WestAirAviation]

I've been flying since 2005 and no one has ever explained this to me. This channel is amazing.

[@TheFlyingZulu]

Lol same... I've always fiddled with that knob trying to figure out what it does but nobody ever knew.

[@AnthonyMartinez]

Thanks for this, I literally asked a CFI checking me out in a club’s Skyhawk what the heck that knob and slide rule were for and they had no idea. My guess was right, but it’s nice to have it confirmed.

[@gulfcoastaero8048]

It’s a major problem with CFIs today.

[@AnthonyMartinez]

@@halcyonoutlander2105 not as scary as the number of commercial pilots shooting RNAV approaches on the opposite end of active runways with full patterns...

[@TheFlyingZulu]

@@gulfcoastaero8048I got my private back in 2005... and just recently started working again on my flight training. My commercial CFI didn't believe me when I told him I could close my VFR flight plan over a VOR by receiving the flight service station over the VOR frequency with the "R" on it... :(

[@abdelabdy9549]

Thank you for this precious video

[@intrepidfox37]

Thanks for the explanation!

[@yeongroksong1829]

I am sorry but I am lost at turning the asi knob. What am I supposed to look at and what to set??? Am I supposed to look at the pressure alt at the top of the asi, or tas plate at the bottom? Please please dont leave me behind!!

[@Yadro767]

Turn the knob to line-up (as best you can) the Pressure Alt with the outside air Temp at the top of the Airspeed Indicator. Once that is set, you can read your TAS on the "white" scale at the bottom of the ASI.

[@yeongroksong1829]

Thank you so much for clarification!!

[@jd1029]

Unfortunately my airspeed indicator is not that sophisticated

[@HAL-xy3om]

+8% per 5000 feet... close enough!

[@johno9507]

So I'm guessing licking your finger and sticking it out the window doesn't work? 🤔

[@engineeringartist4801]

Stuff you pay $125.00 an hour to temporarily remember until you quit flying.

[@sklew]

lmao

[@JoshuaTootell]

$125? A decade ago? 😂

[@kel0ck85]

Screen layout was chopped off at the but I was able to rewatch it & see what you were talking about. Thanks man! Keep the videos coming please & maybe more individualized videos on IFR low charts please for us slow learners.

[@cmurphy3748]

Stupid iPhone notch 🤬

[@marlow769]

Why does nobody simply do the math? 30.17 - 29.92= .25. Since 1” Hg = 1000’ change, this is 250’ difference. Use this number to find your pressure altitude. Then using the meteorological knowledge that from higher than standard atmospheric press to standard, you subtract (or count down to standard) to get the pressure altitude. It’s more accurate and your students learn a deeper relationship between atmosphere, pressure and pressure altitude instead of just some mechanical procedure of dialing down (or up) the altimeter. I really hate the mental laziness of this procedure.

[@TheFlyingZulu]

In the airplane, single pilot with no autopilot I'll use the simplest method thanks... and I'm bad at mental math while flying so this method would be really helpful. Haha.

[@Workerbee-zy5nx]

Pressure and density altitude reall do effect aircraft performance.

[@luichinplaystation610]

But that is basic learning Your instruments are tied to your air pressure in your area or of you're at sea level

[@Workerbee-zy5nx]

@@luichinplaystation610 I flew Cessna aircraft, no computers, so we set our instruments before every flight.😉

[@Factory400]

This is how you justify modern EFIS systems in the panel :-)

[@rustyshackleford2910]

Great review! Haven’t thought about that in years. Fortunately for me all I have to do now is look at the top left corner of my ND.

[@rjobrien7805]

The most important part of this whole video is the temperature scale on the top of the airspeed indicator and it's obscured by the subtitles. LOL

[@Kimeters]

Ive been purposefully using this function of the AI for like 2 years and I never knew that I should calculate the conversion using pressure altitude instead of barometric altitude.

[@christophergagliano2051]

And while you're doing this you actually crash into a mountain cuz you got your head inside the cockpit😮

[@Rod.Machado]

Holy guacamole, you are like that indian guy i watched through out engineering school, you explained everything in such simple manner that i picked it up on the first watch, thank you! You are one helluva instructor.

[@lamylhammoudi103]

I never knew that

[@khfoust1]

I’m not catching the use of the air temp. I see the point of referring to pressure altitudes from Altimeter which you then dial into the upper card in the upper card of the altimeter but how is the temperature factored in?

[@quantomic1106]

Or just add 2% of your airspeed for every 1000 feet of altitude.

[@grayforsyth3728]

Thank you for setting a good example for current and future pilots. Aviation will thrive with love like this.

[@buckyperchski-mc2vo]

Why not set 1000 feet to 2C? Why 0 C if OAT is actually 2 C ?

[@hmabboud]

I did not understand at all. HELP!

[@fromapilotsprespective5814]

horrible advise - hope nobody does this

[@ZenithE8]

Way too fast to absorb or understand

[@Jimmer-Space88]

This is so old-school, no one does this anymore or cares

[@LokiDWolf]

WOW! Very cool to know.

[@finleyfendt3750]

Why is that important ?

[@bakervinci163]

I’ll remember that

[@tmting4942]

u make me smart ✋🏻😃🤚🏻

[@Cosme422]

I love this! 😅I remember going over this briefly in my Sim and paper flight computer before I started real flight lessons, however I’d rather have a G1000 😂 This is a great video! Thank you!

[@blackhawk7r221]

Or use GPS

[@karrpilot7092]

Fly over a road and turn on the GPS function of your cell phone. Works for me.)

[@JoshuaTootell]

Not going to tell you your air speed though.

[@karrpilot7092]

@@JoshuaTootell No, but it will give you the miles per hour. Close enough for me. Also, it's pretty cool doing that. The mile marker signs go by like crazy, and the GPS keeps warning me of potential speed traps. )

[@pk7549]

I like it. In addition, If you're flying something with higher performance, make sure you refrence the static air temp( SAT) and not the total air temp(TAT).

[@alk672]

Yeah these airspeed indicators have a small E6B in them. I guess it used to be useful before iPads for longer cross-countries.

[@59thfsaviation79]

I learned something today. Only bad thing is my altimeter doesn't have an ASI.

[@omarjones1460]

I love these ASI. I wanted to install one in my aircraft but I couldn't find one.

[@RetreadPhoto]

On, I had to watch that like 5 times, but it makes total sense now.

[@andik2329]

I just read it of my screen 😂😂😂.

[@rikardlalic7275]

Great explanation. I just don't understand why you should use the standard 29.92 IN Hg setting to tell the TAS and not the actual ATC/ATIS info at the location, normalised to the sea level?

[@Vejitasei]

You use pressure altitude as the standard datum plane so that you ALWAYS have the same base for comparison. If you used the local altimeter setting (ie ATIS) your TAS would vary as you flew along: different pressure, crossing mountains, etc. By EVERYONE using the same altimeter setting = pressure altitude everyone will calculate the same TAS. This is also way we calculate density altitude from pressure altitude corrected for temperature, not from from the local altimeter setting, so you ALWAYS get the same answer. We can then use density altitude to look up airplane performance.

[@rikardlalic7275]

@@Vejitasei Thank you very much.

[@Amerikanin2numarali_ustasi]

good one!

[@michaelscott1013]

Thank you

[@Blueesteel_]

Oh not confusing at all lol

[@subsoar5734]

it’s… really not. pretty straightforward as long as you have a basic understanding of pressure altitude

[@JohnBorden-fu6my]

thank you for explaining it to me so well I understand the theory but not being a licensed pilot I did not how you figured it out in the cockpit