Flying? What's that?

So...There I was *... enjoying a cup of coffee on a cold Saturday morning pondering how I was going to vote in the current election.  Would I vote for this one, or that one, or another?  What's it to be?  Why would I chose this one?   Questions,  but no answers.

No, Beans, it's not the 2020 Presidential Election!  The only way a democrat is going to get my vote is if I'm dead.  Voting democrat seems to be a frequent occurrence among the post-living voters.

Just sayin'.

No, I was pondering the critical voting on the background photo for the Chant's new header.  In the commentary, Brother Tuna, our Naval representative (No, Beans, not Belly Button representative!  Although....He does sometimes ponder the world in relation to that.) had asked a question about this picture.

Specifically, he posted: "I like #3, but I'm not sure why the Canuck is Strike Lead. Haha."

I had responded that he was flying the slowest airplane.  Which is true.  But it took me a minute to figure out why I knew that instantly on seeing the picture.  The thing that cued me was #3 the F-16.  I started to peck out an explanation, but quickly ran afoul of blogger's comment limitations.

So....Because, Sarge said "You see, we are a blog about flying.", we're going to talk aboot flying. (My best Canuckistanian accent in that last sentence.

Yes, Beans, this is an actual picture of me in flight!
Source

 
The thrust vector (without moveable nozzles) is along the longitudinal access of the aircraft as is, in the opposite direction, Drag.  Weight always points at the center of the earth.  Lift is always applied at a 90^o angle to the longitudinal axis.  Rolling the aircraft around that axis is how you change where you're going.  

Flying occurs by managing the force differential of those vectors, constantly.  Indeed, from Engine Start to Shutdown, it's all about managing force differential.  

Adding thrust (aka pushing up the throttles) gets you out of the chocks in the morning.  Reducing thrust and adding drag gets you back in the chocks when the mission is done.  Similarly, weight pulls you towards the center of the earth, generally stopping you approximately 4000 miles short of that goal.  (Some folks have tried to break the low altitude flying record.  Most of them have only tied it.)  Lift is what changes your direction in all three planes of motion.

But...juvat...how do you create lift?

Excellent question!  And one that took me quite a bit of time in Pilot training to get beyond the 3 step understanding of flight I started with.  That would be:

1) Pull stick back...Rocks get smaller
2) Push stick forward....Rocks get bigger
3) Pull stick back hard.. Rocks get bigger again

But, I finally did.  (I mean, they wouldn't have let me graduate otherwise.)

So, how does lift occur.  Well, the way I remembered it is air molecules are like running buddies.  They have to stay together, but the evil wing comes along and splits them apart one on the top of the wing and the other underneath.  The one on the top of the wing has to run further because the top of the wing is curved and therefore longer.  The molecule on the bottom has a shorter distance to run, so he's got more energy when he gets to the back side of the wing and is therefore able to "lift" the wing.

Trust me, when you get asked a question on how an airplane flies at 3AM in the morning while standing at attention in front of the assembled Instructors and fellow Students, something simple to jog your brain is essential.

But it's also partially true.

So, back to our potential masthead picture.  Look at the right side of the picture.  Notice the smoke trails.  The F-16's is at a different angle than the others, it's pointed down.  Which means that the jet is pointed slightly higher up than the others.    He has to do that because of the airspeed.  If he were to match the other's pitch angle (actually known as angle of attack or AOA), he would not be able to maintain altitude.

AOA is the angle between the longitudinal axis of the aircraft and the forward vector of the aircraft.  (In English, the difference between where it's pointed versus when it's traveling.)  The Canadian jet (CT-114 Tutor, although according to this article, the Snow Birds may change this year) has a relatively straight wing which produces a lot of lift, but also drag, so is a slow speed aircraft.  The F-16's wing is fairly small, 300 square feet, but is built for speed which generates the lift for it.  The only way he can generate sufficient lift to maintain altitude while maintaining a constant speed is to increase the AOA.  Thus, his nose is above the others.

But, juvat, isn't the F/A-18 a high speed airplane also.

Yes. Yes it is.  However, it's got two things going for it.  Much like the F-15 it has a cambered airfoil.  Which means the underside is curved and the shape of the wing is different as moves from the fuselage to the wing tip.  Additionally, the F/A-18's wing area is 500 square feet, so it generates more lift at slower speed.

Found this document when looking for description of "Camber", you should read it when needed to remedy a sleepless night
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That camber and wing size (the Eagle's wing area is 608 square feet), give both exceptional maneuverability at low speed.

So,  if you're going to fly level, but at a slow speed, you've got to point the nose high in the air?

Yes.

But...

Cool site to fool around on at this Source

You don't want the airflow to do what is happening in this picture.  Separating from the wing.

That is called Stall.  Stall is bad.  Stall is what causes "Rocks to get bigger" (#3 above).  The best way to recover from a stall is relaxing back pressure on the stick.  Which is fine if you've got altitude to recover.  If not,  you become one of the many who have tied the low altitude flying record, or hopefully, just the airplane does.



The other way is to power your way out, as the Lawn Dart above does.  He's not actually stalled, but is on the verge of it, and his engine is what is keeping him flying.

This next video describes the actual scientific version of how a wing flies if you're interested.  More precise than my 3AM brain trigger, it is the vector of the air flowing over and under the wing that provides the lift.

But....Lift is Life!

*Standard juvat caveat