Newbie questions re: Learning to turn (and trying to avoid stalls)
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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.
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he did. Post 20.
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Well, its a good thing the FLCS is there to take away that authority from you, isnt it.
Only at high speed…it is possible to depart at low speed if you get ham-footed. And even then, I’m not so certain you wouldn’t get enough feedback for an impending departure at high speed if the rudder weren’t washed out.
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Your rudder authority is decreased with feedback from AoS sensor, so you have to be doing something intentionally dumb.
Then again, playing with the pedals at low speed counts, so there is that I guess.
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…not dumb, unless you don’t know what you’re doing.
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yeah i was actually reading as some of you may have caught in another place i broke my neck and am recouping a surgery so i was reading about this last night i didn’t realize the rudder was basically useless controls in a full digital environ, kinda brings the thought to me of those old “rookie” or " beginner " mode flight models, but if it simplifies while not removing ability its good with me. also, i read a little bit about the afx111 program, and how most of those concepts DONT EVEN HAVE TAILS, and will most likely induce yaws with asymmetric drag from an aileron, or by reducing thrust to one engine.
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…be careful. “useless” is relative - in RL, fully digital Hornet rudders are VERY effective at all speeds…and I’d suspect the one(s) on the Tornado and Typhoon are too. As for tail-less designs, I’d expect even more so as the requirement is to be able to point your nose quickly.
In the digital FCS world there are many design philosophies and approaches…so one has to stick to the specifics of the airframe under discussion.
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within the last few hours i’ve read that in a wings clean super sonic environment, between blocks 20-and 40, boots full of rudder are fine. step up the speed just a bit, into the high 1.5 1.8 ranges and do the same thing with even asymmetric fuel and you might induce a departure, an f-16n put into this environment suffered catastrophic resonance, although I also read it broke up in flight, and the pilot ejected…catastrophic resonance is a phenom in engineering , a wing falling off could be just one weak point, or beyond a crucial failure point. interesting.
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…you’d never actually fight at that speed, so it’s not really an issue. Dash in a straight line to get someplace, yeah…but not maneuver.
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yeah well test is a thing the 416 exists only for it, I guess this was a FOCUS of all midlife upgrades for the 15 16 and 18, as well as an initial cadre departure procedure for the 22. learn something new everyday. there is actually some youtube of the f-16 flight declass. here
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you’ll probably know better, I’m on the outside looking in and around, but I’ve read also that commonly phantom sherk flights would grinder at around 1.7 to 1.3 at 30,000 and the mig cap would be right above them. I know the modern jets are slower and more efficient, but I’ve also read lockheed designed the raptor to cruise at mil power near 35,000 with bays loaded above mach 1.0. Ive also read that with a combat loadout the raptor will continue accelerating up to about M1.4 at 36,000. nothing official because it’s ceiling and acceleration is classified but when they let out the airframe drag coefficients the only thing that beat it was about 40% of it’s size and is a general aviation photographic drone flying wing.
I was reading “smart weapons” which is a book about “the weapons of lockheed, boeing, raytheon/general dynamics” and the list goes on. the last chapter is called “meanwhile at the skunkworks” and it’s all about developing what they call " malleable munitions which can be deployed from supersonic speeds" I don’t know what that means, but someone does. I always like learning new things, but it’s obvious that even the f22 and f35 represent some form of gamesmanship, if we export that RAM there must be something that they keep up the sleeve, especially when it comes to detecting and jamming the new aesa systems and that proprietary RAM.