BFM 101 Understanding Corner Speed

The BVR duel is now WVR and you're in trouble because you don't understand the relationship between energy, turn radius, and turn rate. Here's what you need to know about what they are and how they interrelate to give you your best corner speed.

[@tom434911]

Instructions unclear, ended up at the corner bar... That was the best explanation of corner speed and turn performance I've ever seen. Thank you!

[@oncomms]

I watched this video several years ago. It is the best physics lecture on basic mechanics. It combines everything. I hope same day you can remake this video with the new version of DCS.

[@captain-Dan]

I realise this video is very old it is however VERY informative. Thank you :)

[@Saxoprane]

3 years is not old, BFM is BFM, nothing new even 20 years ago

[@noawe_]

How is this not more popular

[@AlphaCompRepair]

Who would give this a thumb's down? This has to be the best explanation I have ever watched.

[@Flankertrainingcom]

+Fulkrom Someone looking for something with more sex? :) Thank you.

[@fanjerry8100]

Really? Flanker's cornering speed is 540kph? that's a little over half of the F-16's cornering speed at 440 nautical miles per hour, according to the Art of the Kill video. Why such a big difference?

[@nutsackmania]

BLUBLIBLI BLEHHHHHH BLUUUUU BLIBLI BLEHHHHH

[@311Gryphon]

It's on the low end of the power band and 73% of 440 knots. On the high end the Flanker could be doing more like 380 knots or more corner speed. It has a lot to do with wing loading and other factors. The Viper is known to be pretty good at turning and is pretty small and light. I don't think the wing loading on the two planes is vastly different but it is a little different, and there are plenty of other factors as well.

[@imnobodyanon9430]

I wonder if a legit pilot ever came to this channel to study... probably... excellent video

[@Ala13ManOWar]

Yes, even though an old video really clearly and straightforward explained. Congratulations and thank you for uploading.

[@cyberpilot6512]

these tutorials are awesome - Top Gun school...

[@Schimml0rd]

man you have NO idea how much you've helped me... i watched this video years ago and your lesson has helped me _countless_ times

[@BroccoliZombie]

Superb tutorial, thank you

[@Marcin79W]

Thanks mate, great video!

[@eckiger_luki6424]

AWESOME Helped me soo much

[@3RomeoFoxtrot]

very good Vid - thanks and would like to see more

[@juliomontenegro3291]

I've seen your tutorials all these past years... and they are beautifully explicative, along with other American teachers. But now I just find tutorials from Grim Reapers ... that are a real nightmares because his diction is awfully uncomprehensive for me. Please do NOT get lost. Keep tutoring us.

[@peeps000]

this was massively helpful ta

[@ikazuchi-san5772]

Nice video dud helped me a lot Btw just for curiosity: is there any way to calculate the best corner speed for any airplane?

[@GunniesLetsFlyVFR]

Great explination. Learnt a lit and understand this corner speed subject much better. Im off to kill things with the Vipe ;)

[@blainebrixey6264]

New subscriber here! Excellent video!

[@mariecornen2729]

Good stuff,,!

[@paedrufernando2351]

wowoow great .

[@igorputica784]

Best tutorials. Thanks IronHand

[@Flankertrainingcom]

:) You're quite welcome. And thank you for taking the time to comment. Much appreciated.

[@igorputica784]

I remember downloading from site and watching them. Great stuff. Will you be doing DCS 2.5 videos?

[@paedrufernando2351]

@11:34 as you approach Corner speed(which was deduced to be 520km/s at the instantanous corner speed flyby) speed you need to reduced Gs(G's is the demand i.e upward motion you are demanding and that is supplied by the speed at that time (whihc generates the lift)..you need to holde (i.e fly)the speed at the lower 600kms. and so at that point in time when the speed is just at the corner(You can still pull more G's) i.e demand for tha instant turn to kill.

[@3RomeoFoxtrot]

GOOD vid. think they took it from an old Falcon training video where and AF major gave some instruction

[@Flankertrainingcom]

If you're referring to the creation of this tutorial, this was my own from quite awhile ago. I wasn't aware that there was anything like this out there.

[@3RomeoFoxtrot]

kzbin.info/www/bejne/hXSpfotrr5KYmpY

[@JG27Korny]

The alpha (to the left) in the same gauge as the G is not the turn rate but the angle of attack of the wing.

[@Flankertrainingcom]

27 Korny , Umm, where do I refer to it as a turn rate indicator. There is no such indicator in the aircraft. If I did, then I most definitely mid-spoke. But, to be honest, I don’t recall ever referring to the AoA indicator. But I did make this ages ago. So I’ll have to view it again.

[@JG27Korny]

Some people get confused

[@flythething193]

​@@Flankertrainingcom During the Flanker 2/Lomac days I remember getting a tip that an AoA of 18 degrees were a good number to aim for in the Su-27 to maximise the turn performance in a sustained turning fight. It seemed to work pretty well. Btw, I don´t remember you mentioning it either in the video, but I appreciate you uploading them. I think I watched all instruction you had for Flanker 2 back in the day with tracks rather than videos, and a favourite were for example how to defend against the R-33. If you can make videos of them and upload, do it, it´s history! Flanker 2 looked good maxed out when you chose the time of day, and maybe season as well.

[@rongamblin2107]

Sir ! Can you please recommend a good Control Stick. Years ago I had the Force Feedback Sticks in the MS Combat Simulators and Jane's LOMAC . I have just started DCS and of course it's far better than those older simulators. Thanks

[@Flankertrainingcom]

I'm using an X-52 myself. But, as a general rule, get one with as many buttons and hat switches as you can afford. There are a lot of commands to program.

[@rongamblin2107]

Thanks Again !

[@311Gryphon]

Plus one to that. Switches, buttons, and hats are priceless within DCS.

[@Evan_Bell]

So, if one wanted to make a comparison between 2 aircraft, would a lower or higher corner speed be preferable in WVR combat?

[@Flankertrainingcom]

Evan Bell , viewed purely in terms of corner speed, the aircraft with the faster rate regardless of the speed should have the advantage.

[@Evan_Bell]

Right, but for a given g loading, a lower corner speed results in a higher turn rate. A eurofighter at 360 knots (according to unofficial sources) will pull g in a radius of 390m, which results in a turn rate of 27.2deg/s. Vs a gripen with an alleged corner speed of 324knots, pulls 9g when in a 310m radius arc, which results in a turn rate of 30.7deg/s.

[@Flankertrainingcom]

Evan Bell, I have no argument with that. The Su-27, for that matter, comes in with a rate of 28+ with a corner of roughly 325 knots. All I was saying was that “ rate kills” without worrying about the speed. If corner is the slowest you can go and still have the maximum available Gs to make the tightest, fastest turn, then the slower that happens, the greater the advantage.

[@Evan_Bell]

@@Flankertrainingcom Cool. Thanks for clearing it up. Prior to seeing this vid, I was under the impression that a higher corner speed was automatically better.

[@flythething193]

​@@Flankertrainingcom Can you maintain altitude at corner in the Su-27? The Air Combat Tutorial Library (channel) has two videos on EM: "Energy Maneuverability #1 - Spitfire MkIX vs Bf 109 K-4" and "BFM Lesson #3 - Turn Circles & Turning Room (Revised)". In the latter I found out that WW2-fighters can´t do this due to power to weight ratio. Generally the maximum G-load while maintaining alt is around 3,3 and 70 degrees of bank for this type of aircraft. At least in theory.

[@aravindF430]

Trust me I'm a fighter pilot

[@pabilo_]

Hi, maybe someone would be able to help me understand what energy are we taling about exactly? What does it mean that you don't have enough energy for sth. It's hard to find some good explanation anywhere.

[@jasonjaafar]

I'll try my best to explain. Basically, an aircraft energy state is a sum total of air speed (kinetic energy) and altitude (potential energy). This energy is provided by your engines. In order to maneuver, ie change vector, some of the energy is used. Think of Newton's law : An object at rest, will remain at rest until a force is acted on it. This means to change the aircraft vector from a straight flight into a turn, a force is needed to act on the aircraft, in other words you have to spend energy. So in maneuvering terms, in order to turn, you need to expend energy as lift (force) on a horizontal vector (in other words sideways). The more tightly you turn, the more lift you need. There comes a point where your energy requirements will exceed the aircraft's engine ability to provide (in altitude and/or speed). Running out of energy simply means your aircraft does not have the speed needed to generate enough lift in the vector you want (maneuvers). If your aircraft is high on altitude, then to gain energy, you could just dive, converting altitude into speed. But if you are low, then your only option is to fly straight in order to gain energy (speed or kinetic energy). Of course flying straight in an ACM situation is a death sentence. This is just a basic explanation, a lot more intricacies are involved. However this could be your jumping of point into the wonderful world of high performance aircraft (even if it is virtual).

[@pabilo_]

@@jasonjaafar great, thank you, now i get it. It's hard to find anything about aircraft energy. I wanna buy the book about Boyd which'll hopefully give me some more information. *maybe you know any books about this topic? I am open for anything.

[@jaromirandel543]

Imho the Corner speed is 650 (time 9:09) Reason is: In that point you've reached the maximum AoA. The AoA limit won't allow you to pull the stick more than the G limit.

[@dundun92]

Yes I agree

[@dundun92]

Thats exactly when the Gs dropped

[@paedrufernando2351]

1.You need to load up G's i.e keep G's the max possible always loaded onto you airframe(to turn since G means lifting force or the energy required for a turn)..you need that lifting force to enable the best turn which you get when you travel at a faster speed..(i.e good turn rate @7:14) ..so the minimum speed you need is the corner spped..sustained turn requires(which ensures atleast a good minum Gs requied for a fast turn is reserved..and that in the flanker that is about 520 kms)... 2. Now how to keep the sustained turn? Answer is..once you are reaching the corner speed of about 520 kms, ease your stick to reduce G's cos if you hold the G's by keeping the stick yeanked into your lap your corner speed would decrease..and you turn would become instantaneous and you can't keep continuing on the circle that you are making and your speed would deplete immediately and so no more G's aka energy avalible for the tunr..keep the 520 speed by intemittently redcuing G's loaded onto the airframe so that when opportunity strikes you can encash it as an intaneous speed and then kill your enemy. Btw as a side note: whenever you are turning your flight you are putting or turning over your aircraft on one side and turning which requires the energy i.e the G we are talking about..so the more of the energy you can keep in reserve by flying at the corner speed .. you can keep the turn sustained is the simple logic.

[@Jimbo-in-Thailand]

+1 Flankertraining.com - Great easy to understand tutorial! Thanks! 👍😁👍

[@TheNbc27]

How is he reading that his nose was turning at 14 degress per second and so on? I didn't see any sort of indicator.

[@Flankertrainingcom]

There is nowhere to “read it” in the cockpit. That video was created from a track file which I used to make the calculations. I then reported the results in the video.

[@TheNbc27]

@@Flankertrainingcom Ah okay! That makes a lot of sense. How would you go about getting the corner speed for different aircraft then? Would it be somewhere in the flight manual?

[@Flankertrainingcom]

@@TheNbc27 The information is out there for a number of aircraft, either as part of a manual or in various reference charts.

[@stealthtomcat4739]

In real life also Su-27 has instantaneous turn rate of 28 degrees per second.

[@Flankertrainingcom]

Yes, and in the sim as well. That was even true back when I made this tutorial (originally as a voiced track file using Flaming Cliffs 1.x) and years later converted it to video and uploaded it here.

[@nicktolbert9388]

Holy shit that's an old cockpit model

[@Flankertrainingcom]

:) I made that video years ago. We were still flying the LOMAC/FC1.x sim at the time.

[@chadcollier5865]

it's a shame it doesn't quite work that way with JP-4. Tutorial was good, whatever game this is is limited in actual simulation.

[@chadcollier5865]

You have to maintain enough thrust to keep your positive airspeed. Going too slow will create cornering problems due to reduced lift.

[@Youda00008]

And now, what you do against an aircraft with better turn-rate, that's never explained anywhere.

[@Flankertrainingcom]

That was beyond the scope of this tutorial. Against an aircraft with a better turn rate, it'd be a mistake to engage in a turning battle. Use the vertical. If that's' not an option. Run. :)

[@Youda00008]

but vertical turning is also turning

[@Specter0420]

Some planes can turn really well but aren't that great at climbing, in a vertical fight those planes lose where they might win in a turn fight.

[@rakedos9057]

Here lol

[@richt1760]

Youda00008 I believe when he says 'use the vertical', it doesn't generally mean turning in the vertical, but climbing or diving to extend outside of your opponents weapons range, then turning back to reengage, using slashing or 'boom & zoom' attacks. Basically using the strengths of your aircraft to fight on your own terms, and staying away from your opponent's strengths. And running away your aircraft has no strengths compared to his

[@user-mc4li2qm9n]

we need chinese thanks