CRP-5 Calculating Calculate GS, Drift angle, and wind component: Merryface Aviation Groundschool 

10 Years ago?? Man... this video still rocks! Better than my book, thank you man! Much needed!

I've been out of the cockpit for a while and just needed some refreshing RU-vid vids on the CRP to get my mind back into gear. This succeeded mate, very well explained, thanks a lot!

Thank you so much for your tutorials man! You're the best! Happy landing!

Glad I could help. More videos will be up but not very soon. I have my ATP's coming up soon.

I can't thank you enough for this, I really can't! Fantastic! Was staring at my book blank faced! :)

I did the wind calculation in my head. No need for a calculator. Think of a clock face (60minutes) then use the fraction or decimal to calculate the crosswind and head wind. Using your example, 210-170 = 40° 40° = 2/3 (0.66) of 60 Cross wind = 2/3 of wind speed (20kts) = 14kts To workout headwind add 90° to your track in the direction of the wind. 170° + 90° = 260° 260°-210° = 50° 50° is roughly 3/4 20kts x 3/4(0.75) = 15kts You may be out by 1kt but that is trivial. You wont have time to use a calculator when on approach.

Thanks! You explained this far better than my instructor!!

Very helpful video thank you so much!

Is 8kt from the question bank? As I said, my method is calculated, so it's more accurate, therefore it's not going to be exactly like given answers. Just like with the CRP method, which I will upload later, there will be a difference between the suggested and real answers. In terms of accuracy, the equation is best

How about ditching the calculator as well? Remember three numbers: 0.5, 0.7 & 0.9. These are the numbers that approximate to the sines and cosine values for 30, 45 and 60 degrees. Use the closest one and you will be OK. They are close enough for government work and certainly good enough for commercial flying. Their application to groundspeed is self evident. For crosswinds, use these numbers to calculate the crosswind and multiply that by the fraction of an hour that it will take you cover 60 miles. That will give you your drift. For example, given the first case of TAS of 100 kts, track 090 and wind 030/20. Headwind = 0.5 x 20 = 10 kts. G/S = 100 - 10 = 90 kts (close enough). Crosswind = 0.9 x 20 = 18 kts. At 90 kts it will take 0.66 of an hour to cover 60 nm. So drift = 0.66 x 18 kts = 12 degrees (two degrees different). The thing is, with the above method, no calculator is required. You will also find you can do away with rulers and protractors and judge by eye the tracks on a map. Just try it - remember, close enough is good enough. Why? Because the wind forecast is a rough guess, your aircraft's instruments are not accurate enough and an average pilot is incapable of flying so accurately to benefit from such precision. The saying "Measured with a micrometer, marked with chalk, chopped with an axe" comes to mind. So to go flying, all you need is a map and a pencil. Ditch the rest of the crap. Your crooked thumb is 10 nm on a half mill. chart and you always have the marks on the lines of longitude to measure nautical miles. Use common sense and your brain, look out the window and use the 1 in 60 to get back on track.

Thank u so much

Great now i can finally solve. happy landings ...

The calculation for wind components does not always work...for example RWY: 12R Wind: 080°/12 kts shows -8 via your method when the correct answer is 9.2....any idea why? :/

Cos(Wind Angle)*Wind Speed Safes you a lot of time!

great many thanks i can say this save me some brain cells :) if i may add a small note that if true heading is given instead of true track the last part is not necessary... otherwise perfect thanks :D

I got a question for you. TT= 042 W/V=270/21 . I get -14 as an answer using your way. should i just ignore the negative sign in front?

you are awesome..thank you take a subsicribe from me

What if your wind velocity is over 100knots

either way, a 1kt discrepancy is far more than accurate enough to get the right answer in the exam

Hello, if you are showing viewers how to use the CRP-5 that's good, but please use the correct terminology. The term variation is incorrect. In navigation the correct term is DRIFT (not variation). An aircraft drifts in the direction of the wind. Variation is a completely different term, and refers to the angular difference between Magnetic North and True North, and specified as either Westerly or Easterly variation. You also use the term Bearing, the correct term is Heading; and aircraft points on a Heading and moves over the earth on a Track. Bearing refers to the relative position of an object or fix from your present position, measured in degrees true or magnetic. Also you go on to say later in your video, that using the CRP-5 to determine the Headwind and Crosswind components is very complicated; again that is incorrect and the direct opposite to the truth. If you wish to find the wind components, you must use the bottom portion of your LOW speed scale on the CRP-5. It's the bottom area on the slide that looks like graph paper. There you enter the wind vector in the same manner as explained earlier, and just rotate the heading slide to the heading of the aircraft and on the graph is the headwind and crosswind components of 15 and 13 respectively. Very easy and done in less than a minute. Not complicated at all. You're also welcome.

Didn't understand shit lol

bad explanation...

Thank u so much

Thank u so much