Newbie questions re: Learning to turn (and trying to avoid stalls)
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Thanks very much, Stevie, those sound like good, simple rules of thumb. Nice and straightforward.
Turns are making more sense now, and I find that I can avoid high AOA (and stalls) better after some more practice.
I’m getting up to 0.8 Mach before turning, like Mav-jp suggested, and that seems to make me less prone to stalling once I initiate the turn. I just try to keep the FPM visible in the HUD, and that seems to work well, too. I might not be making the best turn at any given moment, but I am at least able to keep turning, and that feels really good after all those stalls. Sometimes it’s a descending turn, sometimes ascending, sometimes I’m at MIL power, sometimes I’m in AB, but at the very least, I’m going around in a circle as though I were engaged with a bandit. As I make these “FPM on HUD” turns, I am playing with making small variations to bank angle, back stick pressure, and throttle, and I think I’m building a little bit of feel for it. There’s a long way to go, but it seems like I’m starting to wire a tiny bit of “feel” into my nervous system, and that feels really good.
I think a big part of what I’m enjoying about Falcon BMS is that it affords a chance to acquire new skills. I find the whole topic of skill acquisition to be really interesting.
Good work! You’re onto it - getting steady on the stick is part of it too. I’d suggest watching airspeed over Mach for maneuver entry though - that’s how most entry conditions are specified. So…vary your altitude, enter a turn at 0.8 Mach, and see/watch how things change wrt airspeed and bleed rate. Good stuff…
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I really enjoyed this book, and helped immensely with my flying generally. What it made me realise more than anything else is the importance of AoA. The author gives a great example of where the Wright Brother’s Flyer had a flag at the end of pole so that they could see the angle of attack. Those boys new a thing or two about flying that was promptly forgotten.
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Thanks very much for the book recommendation, rmax! I just ordered a copy. That looks like a great book for a new, non-pilot person like me to learn a lot of fundamentals from. The “See How It Flies” book on Blu3wolf’s website looks very informative, too.
Years worth of studying and learning to do, that’s for sure!
It would be interesting to know what percentage of F-16 pilots have had prior civil-aviation experience (or even computer flight sim experience) before joining the military. I assume it’s a large percentage, but I don’t really know.
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It would be interesting to know what percentage of F-16 pilots have had prior civil-aviation experience (or even computer flight sim experience) before joining the military. I assume it’s a large percentage, but I don’t really know.
I cant speak on behalf of F-16 pilots, but I can note that the Royal Australian Air Force recommends only a little flight time to prospective pilot applicants. Totally inexperienced pilots will find the first few hours very overwhelming, but experienced pilots will find it hard to relearn how to do everything the air force way. Its hard to break habit patterns. They dont disallow experienced pilots, but they do find that most commercial pilots find it more difficult to unlearn everything.
On the topic of prior experience though, its worth noting that they dont get straight into an F-16 on joining the military. USAF pilots flight training starts out in Undergraduate Pilot Training (UPT), in a T-6. You graduate from that as a qualified pilot, and if you scored well enough to get onto the Fighter track, you go into Intro to Fighter Fundamentals (IFF) in a T-38. Then you learn fighter combat, air and ground. Once you graduate from that, again if there are slots available and if you scored at the top of your class, then you can get into F-16s, in Initial Qualification Training (IQT), and that is followed by Mission Qualification Training (MQT), once you get posted to your squadron.
So by the time an air force pilot gets to training the exercises described above, in an F-16, they already know a great deal of theory about flying, and have a great deal of experience in other aircraft. And they have spent weeks and weeks studying the F-16, how it works, and how it flies, so that none of it should come as a surprise when they do finally get in the air.
For the new simulator pilot, its a lot to take in at once.
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My copy of “Stick and Rudder” arrived, and I’m finding it to be a really interesting book! I’m a little less than halfway through, so far.
I really enjoy reading Langewiesche’s explanations of how airplanes work, in a practical, from-the-pilot’s-POV way. It’s really interesting the way he emphasizes the Angle of Attack. Having discovered - in a crude way - that I was inducing a high AOA during my first attempts to turn the simulated F-16, this really caught my attention.
I also like his writing style. I get the impression that when he first wrote the book, back in the 1940s, he was somewhat frustrated with the then-current ways in which pilots were taught. I gather that he wished a lot more emphasis were placed on the AOA and its fundamental importance. I also like how he’s quite honest when he’s about to give the reader an oversimplified or not-quite-accurate explanation, but takes great pains to justify why he thinks it’s a useful `white lie’. I also love how he tells it straight when he warns the reader that it’s going to take a little while to explain something properly.
Earlier in this thread I speculated that P-sub-S might mean “the sum of kinetic energy and gravitational potential energy”, and I was wrong about that. What I was describing was something closer to “total mechanical energy”, I think. And so I learned a little more about what P-sub-S really is, and how having a positive, nonzero P-sub-S could allow you to do things (like gain altitude during a turn that has certain parameters) that you couldn’t do if your P-sub-S was negative. Langewiesche’s Chapter 3 - “Lift and Buoyancy” - reminds me a lot of P-sub-S, at least in my limited, most-definitely-incomplete way of understanding it so far. I don’t want to go out a limb and claim that “aha, the subject of Chapter 3 is specific excess power!” I’m not sure enough, yet, to make that claim with any vehemence. Need to study this stuff some more. But it sure sounds like it. Fascinating stuff!
And I love the terms he uses for “this mysterious quality” ! He describes how pilots often call it “lift”, even though they don’t mean it the way an engineer does. Then he goes on to propose the names “The Zoom Reserve”, “Potential Excess Lift”, “Remoteness From The Stall”, “Lowness of Angle of Attack”, and my personal favorite - “Firmness of Sustentation” I love it!
Someday I want to be able to say to myself “I got that MiG kill in Falcon BMS because of my aircraft’s superior Firmness of Sustentation at that point in the dogfight”. That would be a total hoot! Would be a great title for a Youtube video of a dogfight, lol.
Tons and tons more to learn, but this book makes learning some of the basic basics of flight a lot of fun.
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Study of the coefficients of lift and drag and their ratio is enlightening. US Navy aviation education is historically superior and emphasizes alpha in a way that land-based did not. They had to understand slow speed flight to operate from ships. Understanding of aerodynamics has a kind of staged progression from lay to civil aviation to naval aviation to aero engineering. The trade off between the pure science of knowing and utility of convention to operate at a certain level is appreciated. A lot of people get caught up in doctrine of a particular school of thought. Ask a lay, pilot, and aerodynamicist what’s a stall and get three different answers all operationally correct to the world they want to apply it to.
P-sub-S, as a physicist, I like to break down into parts. It’s all right there in the name. “P” is power. Power is time-rate-of-energy-change. It’s not E, energy, itself but the rate of adding and subtracting from that bank account. The “sub S” is better appreciated by taking the scenic route. “sub S” means “specific” and it’s called “sub” for “subscript” because they write the S as a little letter below as a label to describe a distinct kind of power, specific power. Specific is used in engineering commonly but in an uncommon way. It refers to the intrinsic property as opposed to an extrinsic one.
An example goes like this: What is more valuable, sand or gold? Gold, naturally. But I have a gigaton of sand and you have a nanogram of gold. My huge pile of sand is worth more, has a greater extrinsic value, than your tiny speck of gold. But you aren’t interested in my particular mountain of sand and your particular speck of gold. You want to learn about sand as compared to gold in general. We invent a new measure called specific value which is the value per a specified amount (e.g. kilogram). Looking at the specific value of sand and gold we compare their intrinsic properties or properties which depend only on the kind of sample object, not the size of it.
An F-16 and B-52 are in a dogfight. The B-52 has a huge potential energy and kinetic energy advantage over the F-16. Think back to physics class E is a function of mass and the B-52 has no shortage of that. It also has a power advantage with 7 more jet engines. Despite this energy advantage the F-16 flies behind the B-52 and wins the fight. Why? For all the B-52s E and P advantages it had a lot of M to haul around. Maneuvering is a function of the E and P divided by mass which are Es and Ps. That’s the specific energy and power or how much energy and power each pound of bomber can call its own. Comparing Es and Ps between the B-52 and F-16 shows why the F-16 won. The F-16 has more E and P per pound of gluteus maximus; it had superior Es and Ps.
As far as “gut feel” words, they have their place. In operation the academic parameters may not be readily accessible mentally. Natural feeling paramters “firmness” “spriteliness” etc. are absolutely valid references.
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need more speed for higher G turning. 400knots, 4G steady is a good practice cause that speed (0.9 mach) and Gs is what you often do in tactical movement.
if you can’t keep it steady within a full 360 turn… then just keep pulling the stick for 720, 1080 or even more till your can make it solid. -
Thanks for posting that video, Ironhead. That really gives me something to shoot for. I really like the way you’re executing those turns. No fuss, no muss, just straight into a 4G turn. The altitude tape stays steady, the airspeed tape stays steady, and the G-meter stays steady, right at 4G. Then a reversal and right into the same turn, going the other way.
Oh, what throttle setting do you use in that turn? Are you in afterburner?
Turn goals for yours truly! I would love to be able to turn my virtual F-16 that way.
So far, I’m pretty far from being able to do it, but I’m practicing. Trying different things, seeing what works, what doesn’t. Hoping to develop the `touch’, someday, to be able to go right into a turn like that.
At present, I’m not getting very close. Bleeding off airspeed, FPM going up or down, getting into “mushing AOA/airspeed”, and the like. But someday, someday, the
touch' will (hopefully) come! Trying to wash off the (imaginary) temporary tattoos on my hands that say "Armour Star". Maybe I should learn the basics of how to change my Cougar's SSC sensitivity, too. I'm still pretty intimidated by keyfiles, the CCP, Foxy, TARGET, and the like, but maybe it's worth taking on those dragons, too, see if that helps. So far I've gotten my HOTAS buttons
realistically’ mapped, purely through the BMS interface. It might be time to take a deeper dive into how controllers interface with the sim. Then again, it’s a poor craftsman who blames his tools… time to cue up another practice session. -
Thanks for posting that video, Ironhead. That really gives me something to shoot for. I really like the way you’re executing those turns. No fuss, no muss, just straight into a 4G turn. The altitude tape stays steady, the airspeed tape stays steady, and the G-meter stays steady, right at 4G. Then a reversal and right into the same turn, going the other way.
Oh, what throttle setting do you use in that turn? Are you in afterburner?
Turn goals for yours truly! I would love to be able to turn my virtual F-16 that way.
So far, I’m pretty far from being able to do it, but I’m practicing. Trying different things, seeing what works, what doesn’t. Hoping to develop the `touch’, someday, to be able to go right into a turn like that.
At present, I’m not getting very close. Bleeding off airspeed, FPM going up or down, getting into “mushing AOA/airspeed”, and the like. But someday, someday, the
touch' will (hopefully) come! Trying to wash off the (imaginary) temporary tattoos on my hands that say "Armour Star". Maybe I should learn the basics of how to change my Cougar's SSC sensitivity, too. I'm still pretty intimidated by keyfiles, the CCP, Foxy, TARGET, and the like, but maybe it's worth taking on those dragons, too, see if that helps. So far I've gotten my HOTAS buttons
realistically’ mapped, purely through the BMS interface. It might be time to take a deeper dive into how controllers interface with the sim. Then again, it’s a poor craftsman who blames his tools… time to cue up another practice session.4Gs and afterburner would mean accelerating unless in quite a climb.
Perhaps your stick is overly sensitive, or perhaps you are a bit ham-fisted. You want a linear response from your stick - no alteration of sensitivity as you move the stick in other words. And you want to be able to make small, precise inputs - a stick which has slop in it is going to make that difficult to impossible. Ideally, you take your hands off the stick, the aircraft keeps doing what its doing. You grab the stick and apply a little back pressure, the nose starts to rise slowly. You apply some roll input, establishing and maintaining a steady roll rate, keeping the stick pressure back, putting the aircraft into a barrel roll. You control the roll rate so as to avoid losing excessive altitude.
If that sounds difficult, it would be worth figuring out if the issue is with the tools or the craftsman. Either way, its something you can fix. If its a control issue, fix it! That might mean repairing or replacing the controller, or it might mean adjusting some settings. If its a pilot input error, you need to take some time to get to know your controls - no one starts out flying like Chuck Yaeger.
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I have been trying to duplicate the turn that Ironhead demonstrated in his Youtube video. Here’s a 10-minute video of me trying to duplicate the same turn:
The first 2 or 3 minutes give the general idea.
My goal is to do like Ironhead did:
Maintain 20,000 feet altitude
Maintain 4G
Maintain 400 ktsIronhead did a remarkable of getting right into the turn, and holding those parameters very steadily. As my video shows, I can’t quite get into a given set of turn parameters like that, and when I do turn, I do a lot of what I’ll call “exploring parameter space”, trying to get into the set of parameters that I’m shooting for. There’s nothing magic about 4G / 20,000 feet / 400 kts, I’m just trying to duplicate the example I was given.
During the first 30 seconds or so of my video (the one linked above), I hold things fairly steady (after a couple of hiccups while getting into the turrn), but I’m not at 4G, and after about 30 seconds, my parameters start to wander. Airspeed drops, and AOA goes up. Then I start hunting around, trying to get towards my `assigned’ parameters.
The thing that fascinates me so much about Ironhead’s demo is that they’re able to get right into the turn they want, no fuss, no muss. It looks as simple as “deflect the stick to the side until you’re at the right bank angle, then pull back to apply Gs”. And maybe that is how they do it. But it’s fascinating to see how well they’ve got that wired into muscle memory - it’s a neat demonstration of what an experienced sim pilot’s skills are like. Somehow, during those few seconds when they’re transitioning from [straight & level] to the turn, they apply exactly the right control movements to take the plane on a “path” through the [bank/airspeed/G parameter space], such that they wind up in a stable equilibrium for a full 360 degrees of turn. And they do it quickly, with no messing around, no experimenting or hunting. Neat!
In my video, we can see what it’s like when an inexperienced pilot tries to navigate the parameter space, and takes the wrong path through it. I wind up in a realm of what I’d call “unstable equilibria” - i.e. flight parameters that end up with varying airspeed, G, AOA or some combination of those things. What a fascinating challenge this is.
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Pulling too much G so your airspeed drops. Solution: less aft stick pressure.
Airspeed rapidly increasing: Not enough G, or nose too low, or too much power (or some combination of the above). Fix any or all of those.
Nose high, losing airspeed: lower the nose, less aft stick pressure.
You were losing speed when holding 4G level at 20K, so you werent going to be able to hold 400 knots. Were you flying the same aircraft, with the same weight and drag?
The thrust matters, the weight matters, and the drag matters. Most all F-16s have very similar drag if they are clean. External stores tend to make more difference than the airframe, with some exceptions. How much fuel you had remaining makes a difference - you get better performance with a mostly empty fuel tank(s). Fuel level and whatever stores you might have been carrying would be likely culprits, along with if you were flying an older F-16 which has less thrust.
As far as controlling the aircraft… it is as simple as setting power, then setting bank angle, then setting G. But it sure helps a lot to be able to do all that without consciously thinking about it, just doing it.
Also, your video makes it look like you have the basic controls sorted out. Id start looking into the aircraft handling exercises and demonstrations from this point. Page 3-40, remember. AHC and HARTS.
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Sorry I haven’t replied in a while, I spent last week hiking and 4-wheeling in the California desert. Took a couple of rest days at the place called “Star Wars Canyon / Jedi Transition” to watch planes. It’s mostly F-18s, but we had a few nice Viper passes, too. Always cool to see and hear jets flying down the canyon. Unfortunately, one of the days I was there was the day after the Thunderbirds crash, so there was the sad thought of the pilot who lost his life, and Nellis was shut down. But jets still flew, and it’s still a beautiful part of the desert.
Thanks for bringing up the issue of weight and drag, Blu3wolf. Ironhead, if you happen to see this message, do you remember the configuration of your jet during the 20Kft / 4G / 400kts turns that you demonstrated? I’d be curious to see if they’re the same as what I’m using, when I go into a dogfight with no opponent plane.
As I’ve continued to practice turns, I’m trying out combinations of side-deflection of the SSC at the same time as starting to pull Gs. That is, pulling both to the side and backwards at the same time. The tip of the SSC would trace out something like half of a parabola as it comes backward. This seems to help a bit, as opposed to purely giving side deflection, then allowing the stick to return to neutral, then pulling back for Gs. My nose doesn’t drop as much, and I may be “mushing” a little less.
Still need to do the AHC and HARTS drills. Those will probably build some good basic `feel’ for how the aircraft handles. Clearly, people like the USAF have a good reason for doing them.
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As I’ve continued to practice turns, I’m trying out combinations of side-deflection of the SSC at the same time as starting to pull Gs. That is, pulling both to the side and backwards at the same time. The tip of the SSC would trace out something like half of a parabola as it comes backward. This seems to help a bit, as opposed to purely giving side deflection, then allowing the stick to return to neutral, then pulling back for Gs. My nose doesn’t drop as much, and I may be “mushing” a little less.
Still need to do the AHC and HARTS drills. Those will probably build some good basic `feel’ for how the aircraft handles. Clearly, people like the USAF have a good reason for doing them.
That is the sort of thing you will pick up as you go along, is adding the requisite aft stick pressure as you roll so as to avoid dropping the nose unnecessarily.
AHC as a section is very much about building that feel for the aircraft handling, as you might have guessed from the name - Aircraft Handling Characteristics. HARTS specifically is more about addressing a serious safety issue for the F-16 training process. It still applies to BMS, but obviously unlike the real thing a crash in the sim doesnt have the same repercussions as a crash of a real aircraft.
The section of training following AHC is BFM, and as an inexperienced viper pilot its quite easy to bleed off more airspeed than you expected to lose in a nose high maneuver. So, its quite easy to end up in a nose high, very low airspeed condition. In the case of the F-16, from this point it is very easy to end up in an out of control situation, from which recovery may be difficult or impossible. This out of control situation is termed a deep stall, and the point of the HARTS exercises is to teach the new student viper pilot how to recognise when this situation may be incipient, and how to recover from an incipient deep stall, without actually losing control of the aircraft.
For the USAF students, they dont actually practice getting out of the deep stall, just getting close to it and recovering without losing control. In BMS though, you can obviously enter the deep stall and try to recover from it without risking an actual fireball.
HARTS specifically does a pretty good job of introducing BMS vpilots to the slow speed handling of the F-16, as well as teaching them how to prevent entry to an unexpected deep stall in their follow on training. AHC as a whole includes a range of other exercises which cover the whole range of performance changes for the aircraft.
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apply opposite rudder when rolling to avoid dipping
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While I dont know of anything specific that says that is a bad idea, it strikes me as not being the best way to solve that issue. If nothing else, its uncoordinated flight for no good reason - but Im not convinced that there is nothing else making it dangerous.
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Applying opposite rudder increases the rolling moment…works better on some airplanes than others as dependent on configuration, but certainly another thing worth playing with. Note - it generally works better at low speed than at high speed…at least that’s what I’ve found.
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you guys have actual time in a seat right im pretty sure i recall reading that at some point maybe im wrong in memory because that’s pretty basic stuff but i can see if your point of reference is a big bad technological bird just as yawing creates a rolling force by itself, and you will eventually yaw into a roll. apply the same logic when banking to begin a gliding turn. I’m just talking basic stuff, mind you this is probably 40 years out of date and not applicable in a hydraulic computer environment. you apply opposite roll to keep a yawing turn level, it’s simply the same logic, applied differently.
If a man goes to school and double majors in psychology and reverse psychology can he learn anything?
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…yes, I’m both a pilot and an engineer…and you can always over-do anything if you don’t know or understand what you’re doing - HART maneuvers aren’t the end-all.
Application of top rudder causes an addition to roll moment in the direction of roll because the center of lift of the vertical surface is at a lever arm distance from the center line of the aircraft body - by applying opposing rudder you create lift in the direction of roll (and a pos-verse pitching moment - for the surface), and therefore an increase in rolling moment. If you over-control (like a rookie may be apt to do…), yes - if you have enough tail authority you can build excessive adverse yaw and may end up departing. Bottom line - you always have to fly the airplane and that means using all of the controls.
My suspicion about the Viper rudder being most effective at low speeds has to do with how it’s limiters work…but in my favorite example of the low level flat scissors, I dance on the rudders constantly - in time with decision to reverse, and even then there’s additional timing involved with application of aileron during the reverse as well - aileron first, rudder next; hence the “lug”. It helps lug the nose over while also keeping my nose high and downrange travel shortened. I can keep this dance up between 120-130 knots before I start to look for opportunities to dump out of it, but if you get the timing right an remain patient you can defensively hold the Mig-29 at bay and eventually to fly past your nose for a gun snap-shot. If you don’t run out of gas first…
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you guys have actual time in a seat right im pretty sure i recall reading that at some point maybe im wrong in memory because that’s pretty basic stuff but i can see if your point of reference is a big bad technological bird just as yawing creates a rolling force by itself, and you will eventually yaw into a roll. apply the same logic when banking to begin a gliding turn. I’m just talking basic stuff, mind you this is probably 40 years out of date and not applicable in a hydraulic computer environment. you apply opposite roll to keep a yawing turn level, it’s simply the same logic, applied differently.
Well, the issue with the technological bird is that the stick controls and the pedals do not command the same inputs you expect flying a non computer bird. You put in a stick command in the F-16 and the flaperons move, as you expect… but then the rudder also moves.
Gets even more complicated the newer you go, but sticking to F-16s at least, its not too complex. The short version is that you generally dont touch the rudder pedals in flight… except for lining up a smart-arse gunshot.
Application of top rudder causes an addition to roll moment in the direction of roll because the center of lift of the vertical surface is at a lever arm distance from the center line of the aircraft body - by applying opposing rudder you create lift in the direction of roll (and a pos-verse pitching moment - for the surface), and therefore an increase in rolling moment. If you over-control (like a rookie may be apt to do…), yes - if you have enough tail authority you can build excessive adverse yaw and may end up departing.
Well, its a good thing the FLCS is there to take away that authority from you, isnt it.
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I’m surprised no one said this yet… but upload an ACMI or video. You are probably doing a variety of things wrong and an ACMI will tell the entire story.