Aces High Bulletin Board
Help and Support Forums => Help and Training => Topic started by: humble on May 02, 2000, 09:07:00 PM
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Read a thread with a post from udie...started me on 190 thought's...I was a
"reasonably" good 190 driver in AW...but I flew the A4 as an E fighter...not as a B&Zer.
When I came to AH the horrible climb rate and fast E loss (compared to AW) made it tough...add trim issues to the equation and I migrated to the pony,nikki,205.
Anyway, pulled it out in the TA at the FFA base for a few runs...pretty clumsy in it...BUT I do see the potential...which brings me to the purpose of this post...I've read 2-3 places about "vector roll's"...this of course after I lent my shaw to a friend (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)...I know basic concept is roll away from cons break...push stick forward as you roll...and stuff plane into the "elbow" of turn...any additional comments..and do you use it?
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I've read 2-3 places about "vector roll's"...this of course after I lent my shaw to a friend ...I know basic concept is roll away from cons break...push stick forward as you roll...and stuff plane into the "elbow" of turn...any additional comments..and do you use it?
Never heard it called a vector roll. What is sounds like is more of a lag displacement roll and yeah I use them all the time especially if im closing too fast on a lower bogie. If Im understanding correctly, you are talking about rolling out of the same plane as the bogie and pulling away from the direction of the bogies travel to gain some separation (the lag displacement) and then rolling back into the direction of the bogies break. Is that what you are talking about? If so, I basically use it to if my AOT is 30 degrees or greater to saddle up for a tracking shot on the bogies six.
If thats not what you are talking about, I apologize (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
-Ding
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Dingy,
Actually i'm not certain, but I dont think it's a lag displacement roll. The 1st time I heard of it was story about Robert Johnson's fight vs spitXIV...guns cold of course (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif). he beat him 1 vs 1 in a T&B fight using that move...he said it was move that he used for most of his kills.
My understanding is you roll away and apply down elevator (push stick forward) at same time con breaks. The P47 out rolls everything so he set early...elevator authority enough to push nose through..he called it "stuffing it into the corner". The way it's described I dont see the seperation of a lag roll...but again i'm not familiar with the move. If you see me in TA can we go fly a few??
[This message has been edited by humble (edited 05-03-2000).]
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I use it all the time in 190,have shown several students this move. You can square off corners in it very well,I usually go into with a nose up attitude to avoid losing too much altitude,roll away from cons break turn and kick hard rudder to stuff it into the turn.
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humble,
I think Dingy is right, that it is a lag displacement roll. It allows fast-rolling planes to 'cut the corner' on their turns. By pushing the stick forward while rolling the aircraft 'sets up' for a turn in the direction opposite the roll. The main purpose of the lag displacement roll is to improve the turning ability of fast-rolling aircraft.
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leonid, Komandir
5 GIAP VVS RKKA (http://www.adamfive.com/guerrero)
"Our cause is just. The enemy will be crushed. Victory will be ours."
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Thanx for feedback guy's,
weazel, since you know/understand what I described, is it a lag displacement roll?
I'm really not sure, I tend to use roll rate in a more limited way since coming here. Obviously, this is an area I have a lot to learn about. Couple question's?
1) What Dingy described seems to be two roll's...away and then back to con, correct or not?
2) Weazel, from what I recall reading, the key element involves pushing stick forward as you roll away from break turn, do you also do that?...also top or bottom rudder?
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What Dingy described seems to be two roll's...away and then back to con, correct or not?
No not at all. Its really a single, slow 300 degree roll away from the direction of the bogies break. As you roll up and away and have completed about 210 degrees of roll (you are inverted and beginning to roll back towards your prey) you begin a bit of forward pressure on the stick to push the nose back towards the target and finish your move now banked towards the target with back pressure on the stick.
Wish I could demonstrate what Im talking about Humble...if I see ya in the TA I will show ya. Rather than two separate rolls think of it as more of a barrell roll.
-Ding
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hehe, I know the feeling Dingy, I appeciate the last post. Helps me to visualize a bit better. when we meet in TA lets fly a couple.
thanx again
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Could the trainers make films of this manouvers and then post them on a site for download? Films like this on the basic and advanced ACM for diffrent a/c would be a great thing.
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Nattulv
2.Lentueen Päällikkö
Lentolaivue 34 (http://www.muodos.fi/LLv34)
"Olen vapaaehtoinen ruotsalainen lentäjä"
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Here is a link to what you guys are talking about , at least I think so that is !
http://www.combatfs.com/warbirds/psiico/tactics.htm (http://www.combatfs.com/warbirds/psiico/tactics.htm)
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air_rules = Play fair ....Don't worry about points......Keep a sense of humor......Drink Jim Beam......and don't let the fediddlein cat walk on the keyboard.......!!!
(http://www.geocities.com/MotorCity/Track/1589/airlogo.gif)
air_squadron (http://www.airsquadron.com)
[This message has been edited by air_spro (edited 05-03-2000).]
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Yup...that link that you posted Air_Spro is the move I was talking about. Shaw calls it a lag displacement roll.
-Ding
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Yup, I read it in a reprinted chapter from Johnstons book...don't know what he called it there...but "vector" roll is what seems to come to mind...think he was talking bout lift vector somehow...anyway thanx guys...gonna fool with it some..i'll try and film em in case I get one right (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Actually, the lag displacement roll Shaw talks about is a slightly different maneuver.
The LDR is used at relatively high angle-off-tail (more than about 40 degrees), where a high yoyo maneuver wouldn't work too well.
Pull lead on the bogey, enter a gentle zoom climb, and start a barrel roll opposite to the direction of your initial turn. You will be able to keep the bogey in sight as you barrel roll above him. Wait till he passes beneath you, and pull down onto his high 6.
The 'vector roll' was used in low AOT situations. Although the move is often attributed to Johnson, his book does not really mention THAT maneuver at all!
He talks about 'skidding' his aircraft away from the bandit's turn, whilst rolling 90 degrees towards the bandits break - then pulling hard inside the turn.
What I think he was actually doing was skidding the aircraft slightly away from the initial flight path, allowing him to cut inside the turn even though the P47 had a larger turn radius than the 109. By skidding his aircraft he is displacing his flight path laterally - then drive to the corner, pull hard and bingo!
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C.O. Phoenix Squadron
http://www.users.bigpond.com/afinlayson/index.htm
'feel the heat .......'
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This is funny. Ive been doing this since my ACA days. I didnt know it was a real move. Even has a name.
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Hmmmm... I've always called it a 'roll-away'. Used and timed right it sticks me where he can't see me, minimizes my e loss while his is high, gives me enuff seperation to delay the chips being cashed outright while follwing his break and no matter what the guy does; he's toast if he's tryin to manuver. Defense against the rollaway is NO turn.. extend.
FW's hate it when I use it on 'em. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Hang
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Sigh, me stipido, not understand.....need to see , Will shout in TA (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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I use this move ALL the time. It's good when fighting something like a spit in a plane with slightly inferior turning ability, like the 205. Usually I'll come in from above on the spit, and end up on about his 8 o'clock. Because I have more E, I cannot possibly hope to turn with the spit, so I roll away from him, pull up for a little separation, then roll back in on his 6. (Usually you are inverted when you complete the manuver.) It's great if the other plane is at a slight E disadvantage, as it allows you to keep an altitude and speed advantage on the bogey.
I'm pretty sure this is what you have been describing. It kind of looks like a lazy barrel roll on film. E fighters are great for this as you turn mainly in the vertical while the other guy is flat turning. 109g10 and the c205 are great for this because of their great climbing ability. Roll rate isn't too important, as you really don't roll that fast when doing this.
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bloom25
THUNDERBIRDS
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From your description bloom that is a kind of aborted barrell roll attack. You come in from higher at a shallow angle from 7-8 or 4-5 and start to turn toward the bogey. As the bogey breaks hard, you pull up shallow for vertical separation and check that the bogey is continuing his turn.(Or not... you can't always check if you want to do it fast enough, sometimes you have to do it blind.) The way bloom mentions it he simply rolls back and turns it into a high yoyo, which is better than a flat turn. To do it properly is harder, but works better. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
So you've pulled toward the bogey, pulled up say 30 degrees and checked the bogey. You see the bogey continueing his flat break turn so you know you can do the rest of the attack. Either that, our you gamble that he's going to do it, and pull it off blind, not the best method but sometimes works best. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) Next comes the weird part... you roll away from his direction of break and start a downward spiral in the other direction using roll in the verticle to point your lift vector at where the bogey will end up after his break turn. Then you just pull out of the dive gently and if you timed it right, you drop right on his six or even ahead of him for a snapshot. It's one of those things that's hard to describe, not intuitive, and hard to do. When it works though, it's magic, and it works more than you would expect. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) When you start doing it right you'll get the "You cheater, you out-turned my Spitball in that Hog!" calls a bunch. That's when you'll know you did it right. <G>
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Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
http://users.andara.com/~sconrad/ (http://users.andara.com/~sconrad/)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
- Steve Earl
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I think you're right Lephturn, that's a better description of what I'm doing. Usually I use it when attacking a n1k or spit in a plane that doesn't turn as well. In this case you usually have a huge E advantage, and you want to keep the fight close without losing your E advantage too quickly. (All I know is I can't do anything right this tour... (http://bbs.hitechcreations.com/smf/Smileys/default/frown.gif) Have you ever had nights where everytime you shot down a plane, you ran into his burning fuselage. Then he gets the kill on you. LOL I had it happen 3 times in one night.)
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bloom25
THUNDERBIRDS
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I used to use this maneuver a long time ago in the Fw 190 in WB. While roll rate may not be crucial in bloom's case when energy is oozing out of the rivets of your aircraft it can be more crucial when E levels are more equal. The reason is that one may not have the luxury of using the vertical against a hard turning opponent which holds equivalent energy. A quick LDR may give you that nice 60 degree snapshot, and only a fast rolling aircraft will get you there in sufficient time.
The funny thing is I haven't used LDRs in the la5, which has a very nice roll rate especially around 300ias. Maybe this will be my meal ticket for all those spits, 205s and nikis! Thanks for joggling this old, abused brain (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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(http://www.adamfive.com/guerrero/5GIAP.jpg)
leonid, Komandir
5 GIAP VVS RKKA (http://www.adamfive.com/guerrero)
"Our cause is just. The enemy will be crushed. Victory will be ours."
[This message has been edited by leonid (edited 05-11-2000).]
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Very interesting links. (http://www.combatfs.com/warbirds/psiico/outsideroll-1.jpg)
This is I think what was initially being discussed.
This one:
(http://www.combatfs.com/warbirds/psiico/Johnsontactic.jpg)
Is not what I mean by a barrell roll attack. It is simply a modified version of Johnson's outside roll move with some verticle thrown in. Basically he is rolling out to get angle without closing on the bogey too fast and overshooting. Notice in the description he mentions the 109 pilot chopping throttle. This is a good counter to a better turning plane that goes for the defensive spiral, as long as you get the shot at him early enough.
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Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
http://users.andara.com/~sconrad/ (http://users.andara.com/~sconrad/)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
- Steve Earl
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Hi,
perhaps you should look at this short video:
www.lemsko.de/video/lagroll.rm (http://www.lemsko.de/video/lagroll.rm)
Macchi
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www.lemsko.de (http://www.lemsko.de)
ACM Training videos
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Couldn't open that site, I'll try later.
In the mean time, I've been talking to some of my squad mates. Among The Flying Pigs lurk some great ACM masters such as Worr and Eagl. Eagl is a USAF pilot who has flown F-15's as in currently working on becoming an instructor. He emailed me what is easily the best description I have ever seen. What follows is reprinted with permission, and email from Sean "Eagl" Long.
----- Begin Quote --------
Those diagrams are really showing what we call "offset turning circles".
Rolling in the opposite direction is simply creating some turning room for
the pursuing fighter, offsetting the turn circles so that the circles will
meet again on the far side of the circle.
A better method of offsetting the circles would be to pull up and maybe
slightly away, using the vertical to gain your turning room, then quickly
turning back in the direction of the bandit. The turn circles are now
offset, and the result will be a snapshot opportunity just like the diagrams
show at the end of the depicted manuvers. The beauty of rolling the wrong
way is that it ensures that the fighter doesn't delay turning back in too
long, but a little discipline can fix that problem, and pulling up and
slightly away (but not too long!) becomes a better way of getting the
required offset.
To see what I'm talking about, imagine 2 hula hoops, one 3 ft in diameter
and one 4 ft in diameter. Hold them both with one hand. You can see that
the hoops touch in one place (where you're holding them), but after that the
3 ft hoop is inside the 4 ft hoop the entire rest of the circle. This
illustrates the turn circles of 2 unequal performing planes that start at
the same spot. Now take the 4 ft hoop, and move it in one direction or
another so the hoops cross in 2 places (like the overlapping Olympic games
symbol). This illustrates "offset turning circles". Now with the 2 hoops
offset like that, imagine 2 planes racing around the hoops. At one spot
around the hoop (the crossing right after the area where the 4 ft hoop is
OUTSIDE the 3 ft hoop), the 4 ft circle plane will have a snapshot at the 3
ft circle plane, and at the other crossing spot around the hoop the 3 ft
circle plane will have a shot on the 4 foot hoop plane.
The trick for the 4 ft circle plane is to get enough turning room at the
spot where the 4 ft hoop is entirely outside the 3 ft hoop so he can turn in
cutting inside the 3 ft hoop's circle, and get a killing shot. How you get
that turning room is up to you, and the more room you get the higher angle
the snapshot will be. The diagrams and WWII tactics seem to show that the
offset is gained by rolling first away from the bandit then rolling back in,
but the same thing can be done without losing sight of the bandit by rolling
only slightly away and climbing, gaining you both lateral and vertical
turning room. This would be a classic high yo-yo btw, and the manuver might
only take a second or two. If you also have vertical turning room in
additional to lateral turning room, it will do a few things for you. First,
since you're going down hill, you will sustain energy better and your 4 ft
hoop will shrink to a 3.69 ft hoop (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) Second, your turn circles will cross
or align for a slightly longer time since you're turning harder, and you'll
get a longer snapshot. Third, since you moved up, there's an increased
chance of your stupid flat-turning opponent losing sight of you.
Note that at the first time the circles cross (after the spot where the 4 ft
hoop is outside the 3 ft hoop) the 3 ft circle plane has turned more angles
than the 4 ft circle plane. The more offset you have, the greater that
angle difference becomes and the briefer the snapshot opportunity will be.
Taken to the extreme, if the offset is too much, you will meet head on.
More on that later.
Offset turning circles work regardless of the plane of motion of the bandit.
For example, if you imagine the hoops standing up on edge, you're seeing
offset turn circles in a looping fight, and the only difference there is
that the hoops should be egg shaped (fat at the bottom, skinny at the top)
because of gravity effects. It's even more interesting in a looping fight,
because you can offset vertically (if you're bounced) or laterally (if you
engage a looping bandit from co-alt setup) and the amount of time spent
vulnerable or in firing position will change depending on the setup.
The last trick to an offset circle fight, is for the inferior turning
fighter to give it up after his snapshot. With an offset turn circle, the
inferior fighter might THINK he's winning the turn fight, when instead he is
simply reaping the benefits of the offset circles. Even one half of a
circle later, he may be defensive as the circles cross again. The solution
is after the initial snapshot, the inferior turning plane must do something
to reposition his fighter, either changing the plane of his manuvering or
extending for another entry. If he has kept his speed up, he could roll
wings level and pull up into a loop. If he has sufficiently scared the
bandit, he'll again suprise him as he comes back down the other side of the
loop. If the bandit has any SA and remains undamaged however, the bandit
can reverse his turn, go vertical with the fighter and nail him at the top,
or transition to a spiral climb which will "stuff" the fighter at the top
without enough offset turning room. Remember the bandit was taking fire in
the first place because he gave the fighter turning room, so if he's smart
he'll do whatever he can to take away that turning room by not letting the
fighter get far enough away to turn in for a shot.
The extreme of an offset turn circle fight is a classic head-on merge 2
circle fight, where the fighter and bandit make an HO, both make left or
right turns, then HO again. In that case, the circles are offset so far
that there is only one spot where the circles cross, at the HO merge. This
is a losing proposition for the inferior turning fighter, because eventually
the superior turning bandit will get turned around fast enough that he can
shoot, while the fighter can't get his nose around in time for even a
minimal snapshot. Use of the vertical at the initial merge can help the
fighter if the bandit makes a flat turn, but if both fighter and bandit go
vertical (making it a single circle vertical fight), the superior turning
bandit will get his first shot before the fighter tops out of his loop.
Doh... Is that long enough? (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
eagl
/('o')\
----- End Quote -------
Wow, that certainly simplifies things and puts it all in perspective. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) Having USAF (soon to be) instructors lurking in the community is a big plus. <G> I'll be turning this into an article for my web site as well, so this great piece of training info will not be lost!
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Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
http://users.andara.com/~sconrad/ (http://users.andara.com/~sconrad/)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
- Steve Earl
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A footnote - I forgot to let everyone know, but I passed my last instructor checkride on 28 April. I've been working as a line instructor since then. I haven't really scared by my students yet, but it's only a matter of time (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) Fortunately the guys I'm teaching right now are almost done with the T-37 phase, so they're not bad at all. In a month or two, I'll be teaching the brand new students and it will be a whole different ballgame.
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eagl <squealing Pigs> BYA
Oink Oink To War!!!
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Wow,
Thanx everyone for the input, obviously this is being used alot more than I recognized. only thing I can think is since I never flat turn (well almost never (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)) is that I dont see it in the horizontal. I'm very certain from eagls description i've seen it more than once in the vertical...I am trying to envision it's use in the classic "out of plane" merges where both planes are oblique ( hope thats stated correctly ) got 1 more trip then i'll be back up, hope to work on this some...thanx again all
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Congrats, Sean!
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John Sponauer
Senior Editor, SimHQ.com
jsponauer@simhq.com
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Great posts, Lephturn & eagl!
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(http://www.adamfive.com/guerrero/5GIAP.jpg)
leonid, Komandir
5 GIAP VVS RKKA (http://www.adamfive.com/guerrero)
"Our cause is just. The enemy will be crushed. Victory will be ours."
[This message has been edited by leonid (edited 05-12-2000).]
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Sean
Welcome to Squeaks!
My first class was with guys who had just finished their first contact check. My next class was my first pre-solo class. I can still remember my first student's solo. As circumstance would have it, he and I would meet again some 15 years later...he as an Aggressor pilot and me in my Hog. My dimming memory fails to account how it turned out!
I'm still amazed that the 37s you are flying are the same ones I flew as a student...with some very nice upgrades since. At least you don't have to put your gear down in the GCA pattern to improve your chances of being picked up. I know...what's a GCA pattern, right??!!
I always remember the 37 as an easy airplane to fly and a difficult airplane to fly well. One of these days, you'll come down initial and announce to your stud that today is a XX% day. You'll set that RPM in the pitch and won't touch the throttles again until you pull them to idle in the flare...and you'll have the textbook numbers all the way around the downwing and the final turn. He'll be amazed!
Best,
Andy
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Back on the subject of the 'barrel roll attack'....
BFM terminology tends to change over the years...sometimes it gets confusing when two people use the same term but are talking about two different things.
In BFM, you are basically trying to solve two problems...fuselage alignment and closure. All of the individual maneuvers are meant to handle one or both of those problems.
One of the easiest to categorize is the Low Yo-Yo. This maneuver is primarily designed to increase relative closure, both as a function of increased airspeed and (if the bandit is turning) lead pursuit arcing. This maneuver used to be referred to as an 'acceleration' maneuver.
When we start dealing with angular problems, the situation gets murkier. For one thing, terminology has changed over the years. As a result, definitions tend to be the source of debate (that's the nice way of saying argument).
Way back when...we used to teach something called 'rolling maneuvers'. These came in a number of forms...vector rolls, barrel rolls, lag rolls, quarter planes, high yo-yos, high G rolls under (and over)...these were used to solve aspect and closure problems. In some cases they were interchangeable; some were offensive, others primarily defensive.
Having said that, the crux of the problem as outlined in the original post is fairly simple...the attacker's turn radius exceeds the defenders. One thing that never changes is Physics...turn radius is a function of true airspeed and radial G. No amount of smoke and mirrors can change that!
The attacker can do one or both of two things. One...he can improve his own turning performance by possibly slowing down if he was above corner velocity, or improving his plane's ability to produce lift by lowering flaps, or two...he can maneuver out of plane. It's this second choice we are talking about.
First of all, all out of plane maneuvering is, by definition, lag pursuit. One way of looking at lag pursuit is 'slowing things down now so I can speed them up later'. While lag maneuvers may be used to control closure, they usually deal with an attempt to gain additional turning room...either outside the bandit's turn or above/below the plane of his turn.
In the example given, the details are unclear as to what the P-47 pilot was actually doing. I suspect it was one of two things.
He may have been going for additional lateral offset while still behind and in the plane of the bandit. This extra offset then becomes added turning room as the bandit starts his break. The P-47 pilot then drives forward towards the extended deep six of the turning bandit. Approaching it, he then starts his own hard turn.
Or...he could be describing a rolling maneuver that looks like a combination of high yo-yo and barrel roll. The yo-yo gets him up and out of plane (lag pursuit) and the unloaded roll allows him to preserve angle off in the climb. The result is a nose high position still in the bandit's six with the lift vector now oriented back into the bandit's turn (lead pursuit. From this position, the P-47 driver slices down into a guns track position.
One thing for certain...there is no in- plane, 'forward stick', rolling maneuver that can change the physics of the situation. In-plane, constant speed, turn radius reduction can only be achieved one way...lots of G!! I doubt that WW2 pilots were maneuvering with negative g loads as high as the description implies...neither the pilot nor the a/c was stressed for it!
Anyway...a lot of this is pretty advanced for our sim flying. Some of the real world maneuvers are not possible to fly properly in our sims...for two reasons. One, the flight model is incorrect (rudder effectiveness at high AOA is a good example), and two, our viewing systems do not give us the 3D SA needed to fly the maneuver.
I think you have two choices...either yo-yo off to get some vertical turning room, or, if able, pull additional lead for a snap shot.
Andy
Ya'll stop by the Air Combat Corner at www.simhq.com. (http://www.simhq.com.) I've got a number of articles there that try to explain BFM in wys that you can use in your sim.
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thanx for the insight Andy, i first read about the "vector roll" in a couple of excerpt's from WW2 "memoirs" years ago...I was wondering where i saw it recently andjust found it again...a buddy of mine was out here for some golf R&R and i indroduced him to flight sims...he wont forgive me for years (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)...anyway he like most newbies has a long road ahead..and he lobbied for all my boxed stuff..i never touch em anymore..low and behold the "vector roll" is in the janes tactics part..page 67 or such.
My confusion in the orginal post alludes to your post...I was/am still somewhat confused with regard to the out of plane element (not clearly described anywhere) vs the hi speed roll of the 47...johnston was quite clear that he was using the roll rate to defeat opposing planes with surerior cornering but inferior rollrate...obviously this involves out of plane lag manuvers (least from my semi-novice perspective).
The exact quote is as follows...as the aircraft your tailing starts his tight turn,roll away from the direction of the turn and then throw the stick forward...The end result is that you swing underor over your opponent and push the nose to the completion point of his turn.
What seems missing in this simplistic explanation is the initial positioning...both on the x and y axis with regard to con...and the AoA at initiation of the move ...obviously lot of components in the setup.
thanx again for all the help with this ...i'd love a clip if anyone happens to pop one of these of in the arena.
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Humble
I don't understand the quote either.
I don't claim to be the expert on BFM but this technique has me confused. The mechanics of what Johnson appears to be saying just don't match up to anything I know in real life.
There are some idiosyncrasies of WW2 a/c that we don't see today...torque effects, for example, that may affect BFM in a manner that a jet would not be able to duplicate. But, I would need to see a more definitive explanation of this maneuver before I become a believer!
Andy
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The mechanics of what Johnson appears to be saying just don't match up to anything I know in real life.
OK, a quote from 'Thunderbolt!', by Robert S. Johnson (at p. 216)
"The pilot is desperate. He flings the airplane about, suddenly snaps the Messerschmitt hard over to the left. No good! My foot slams down on the rudder, easy on the stick, and the Thunderbolt skids cleanly. Now - roll! The P-47 responds like a thoroughbred, flicks around. Controls back, a sharp turn and the eight guns loom broadside to the target, One short burst, eight streams of bullets converge, and the Me-110 tears apart".
My reading of this maneuver? No vector roll, no lag displacement roll.
Imagine Johnson and the bandit are heading due north before the turn begins. The bandit breaks left. Johnson hits hard right rudder and skids the Thunderbolt to the right (east), but his aircraft is still pointing north. He's building lateral displacement which he can use to negate the 47's turn radius deficiency, in effect offsetting the centre of his turn to the outside of the 110's turn centre.
The roll advantage comes in here. Since the 47 can roll faster than the 110, Johnson can keep his skid going for a longer period of time, and still roll 90 degrees left by the time he reaches the elbow of his opponent's turn. Had he been flying an aircraft with a slower roll rate, he would have had to break off the skid earlier in order to be wings vertical at the elbow, thus generating less lateral displacement.
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C.O. Phoenix Squadron
http://www.users.bigpond.net.au/phoenix
'feel the heat .......'
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The more I read that passage by Johnson, the more it sounds like a controlled high AOA snap roll or spin entry used to set his initial turn direction. In the F-15E, we can get an amazing initial turn rate by doing something similiar. Basically you pre-load the aircraft, either in yaw or pitch, then in the F-15E, you trick the flight control software into snapping the nose abruptly one way or the other. We can move the nose approximately 25 degrees in pitch, and then can snap the nose almost anywhere around at least a 25 degree cone around our flight path. This is what we call a "vector roll", rolling (it's actually more like a yaw) around our flight path at an extreme AOA. The F-22 and F-18 can do this up to and beyond 45 degrees AOA, although the F-18 is thrust limited and can't keep doing it long before it falls out of the sky.
It's possible to do it in WB as well, especially in the P-38 and F4U, but it's difficult. The P-38 move in the game was perfected by mili then copied by many others. It's almost impossible to describe, except as a controlled spin entry with the rotation halted after about 180 degrees, then the plane is flown out heading in the other direction. I haven't tried it in AH because the more lethal guns in AH mean giving your opponent even a snapshot opportunity generally means virtual death.
Back to the P-47... Imagine this. The P-47 rudder allows it to skid, say... 10 degrees off of it's actual flight path, in this example to the left. Once stabilized in that skid to the left, a 90 deg left roll is made. Guess what? The plane is now flying along with an instant 10 degrees AOA (the previous slip angle) in a 90 degree left bank, except since he still has a bootfull of rudder, the nose is also pointed an additional 10 degrees down, for a net gain of some 20 deg instant nose position. This was apparently enough to help put the guns on target. This kind of thing can be used to combine small nose pointing abilities into relatively large nose position changes and the ability to immediately set the lift vector where it belongs.
On another subject...
Andy, you're right about the new gadgets we have to play with. We have this new thing called "radio" so the tower can tell us we are allowed to takeoff and land without shooting flares at us, and our "radio" is so high tech that it only has 9 dials, knobs, and switches. We recently got something called "TACAN", but since that would confuse our poor overloaded students, they put a simple "DME" display on the panel so it only gives range and a radial. It seems that our old "VOR" still has a few decades of lifecycle still, so they didn't want to tie the "TACAN" to the needles and dials.
The manual describes something called "ADF", but it must cost too much because our jets don't have it installed.
Isn't it amazing how these modern, 50+ year old planes never seem to get older? Half of our fleet survived a severe hailstorm, and after some touchup paint they were back flying again. I guess all the dents on the skin reduce drag just like the dimples on golfballs make them fly farther.
I've already had my moment of final approach Zen... We were leading a formation approach and Stanley (ya know, Stanley Student) couldn't figure out what power settings to use to keep 110 configured with speedbrake out on final. It was a warmish spring day, so I told him "quit messing with the throttles, just set 87% and it'll hold 110. And %76 will hold your 3 degree final just fine too." It worked as advertised, and as usual he thought it was magic (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) It's amazing how the little tricks almost ALWAYS work out within a percent, but that's the beauty of the tweet. I wonder how long it'll be before the new T-6 is known as well.
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eagl <squealing Pigs> BYA
Oink Oink To War!!!
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Jekyl
Yes, that is exactly how I imagined it. A skid (or something) to increase lateral spacing and then a hard pull before he overshot the extended six of the slower turning bandit.
The 'stuff the stick into the corner' sounded like a lot of bar talk...or somebody was referring to something else.
Thanks for that additional quote..that cleared the matter up.
Andy
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Eagl
I know the vector roll that you refer to. The F-4 had an amazing rudder...and we could rotate around the flight path at high alpha as you describe. But you did bleed knots, so the maneuver was great for quick decellerations...like overshooting an F-5 at your six, for example.
When I went to the F-104, I had a surprise waiting for me. On one of my first formation rejoins out of traffic, I cane slamming in as I was used to in the F-4. Then it was idle, boards, and opposite rudder to kill the speed. In the F-4, the thing would come to a shuddering halt. In the F-104, it was a bit different. I had never overshot lead so bad in my life! The 104 rudder was an afterthought and had practically no effect. Vector rolls in the 104 were not very effective as a result...unless you could get enough alpha to pitch the thing up...then it slowed down real well <g>.
I flew Tweets out of Laredo, 69-72. Where are you at?
Andy
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I'm at Sheppard AFB, Euro-Nato Joint Jet Pilot Training. Since the Germans own most of the planes on the ramp, we'll be the last ones to upgrade to the new primary trainer and (I think) our T-38's will also be the last ones to get upgraded as well. Both the T-6 and new T-38 are supposed to kick bellybutton (as far as trainers go anyhow), but I'm at the wrong base and a few years too soon to see either of them.
If you try using rudder in the F-15E during a rejoin, you're asking for an autoroll if you overshoot. With cross-controls (aft stick, aileron one way, rudder the other), if you push the stick forward (step 1 in an overshoot) without releasing the rudder first, the plane will get some pitch/yaw/roll coupling and will enter an uncommanded "stabilized" roll all on its own. Centering the controls is ineffective, and to get out you have to use opposite rudder and hold the stick slightly aft of neutral. A friend of mine entered an autoroll before the dynamics were fully understood, and during the recovery the stick ended up a little fwd of neutral. The result was a -7 G pitchover (ouch) that nearly destroyed the plane. He limped the plane home but repairing it required an almost complete rebuild. His experience resulted in several new pages in the -1 fully explaining several weird handling characteristics of the F-15E.
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eagl <squealing Pigs> BYA
Oink Oink To War!!!
[This message has been edited by eagl (edited 05-13-2000).]