Cupping

"How To" by our Pilot Staff
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Lawndart
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Cupping

Post by Lawndart » Wed Jun 21, 2006 6:53 pm

Two pics illustrating what cupping is. Note the left and right wingmen banked inboard towards Lead. Just happened to be the Blue Angels, could have just as easily been any demo team...

The Thunderbirds fly their formation characteristically flat, rather than changing to the deep stack formation the Blue Angels use. The flat formation appears more like four (or six) ships in unison, especially in rolling maneuvers (Note: these two pics are from rolling maneuvers), while the deep formation facilitates greater overlap, thereby making the aircraft appear tighter from certain aspects.

While deep stack vs. flat formation is one thing, these are some of the best pics I've seen showing what a "cupped" formation looks like.

LD

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Post by Airshow fan » Wed Jun 21, 2006 7:14 pm

As much as I know about the Blue's I never knew that.
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Vladimir
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Post by Vladimir » Fri Jun 23, 2006 1:10 pm

Interesting observation, Lawndart.

What could be a factor in this case?
Maybe the roll rate is a bit higher than usual?

BTW, I noticed that the Blue Angels 2006 are flying a tad "eased out" formations compared to the 2005 team at a similar point of their season.
But still, they are one of the best aerobatic teams :)
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Post by Lawndart » Fri Jun 23, 2006 2:40 pm

Vladimir wrote:Interesting observation, Lawndart.

What could be a factor in this case?
Maybe the roll rate is a bit higher than usual?

BTW, I noticed that the Blue Angels 2006 are flying a tad "eased out" formations compared to the 2005 team at a similar point of their season.
But still, they are one of the best aerobatic teams :)
Unless it's by choice (which it could very well be for some teams), cupping is typically a side-effect of not using enough rudder input towards Boss. Every team has it's own way of doing things from year to year and a lot of it has to do with technique even though the procedure is the same as the previous year.

The other side-effect is called toeing which means you're putting in too much rudder and basically pointing your longitudinal axis inward towards Boss. One or the other is almost a necessity for fast roll rates, but the combination of being slightly angled (yawed) towards Boss and a little cupped makes it look almost symmetrical.

In a flat formation (i.e. Thunderbirds) you're more likely to see some toeing and in a deeper stack (i.e. Blue Angels) the pilots are more prone to cupping.

As far as the tightness of formations at certain points in the season. Not factoring in any weather conditions or other external factors that would cause them to choose to fly more spread (for instance a lot of texture in the air or bumps), it's based on the review and evaluation of prior performances. With continuously good grades, they tighten up and fly lower etc which is normally why the last two months of the season are the best to watch them! Then again, some teams in the past were more talented and flew better than others, just like some pilots were better than others. Although, the only ones good enough to do it right now are the guys on the current team, so if you ask: Which team is better? The current team is really the only true answer!

Lawndart

P.S. If you find a video clip of a Diamond Roll by the Thunderbirds or even the 90 degree roll at the top of the Clover Loop, look at #3 (right wing) as he's rolling and you'll see his nose yawing towards Boss. Best example of toeing there is and as far as the Thunderbirds go with their characteristically flat formation and really fast paced roll rates, it is very common for the right wing pilot since he's always being rolled away from given that all rolling maneuvers are done to the left. The way they manage to mask or hide a lot of this is because as the formation hits it's highest roll rate they are edge wise to the crowd and from the ground perspective you cannot notice the toeing at that point. As they come over the top of the roll and inverted #3 has to ease out some rudder and cup more to make it look right from the ground view as he maintains his spacing. I think you get the point!? Obviously cupping is less desirable for a Delta formation compared to a Diamond since it "shadows" Boss from the outer wing positions. Contrary to what the right wingman does, the left wingman typically flies more cupped in rolling maneuvers, given that Boss is continuously rolling into him (not a good idea to have a boot full on the rudder at that point when someone 3ft away is rolling his airplane at you).
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Post by Vladimir » Fri Jun 23, 2006 3:45 pm

Lawndart wrote:P.S. If you find a video clip of a Diamond Roll by the Thunderbirds or even the 90 degree roll at the top of the Clover Loop, look at #3 (right wing) as he's rolling and you'll see his nose yawing towards Boss. Best example of toeing there is and as far as the Thunderbirds go with their characteristically flat formation and really fast paced roll rates, it is very common for the right wing pilot since he's always being rolled away from given that all rolling maneuvers are done to the left. The way they manage to mask or hide a lot of this is because as the formation hits it's highest roll rate they are edge wise to the crowd and from the ground perspective you cannot notice the toeing at that point. As they come over the top of the roll and inverted #3 has to ease out some rudder and cup more to make it look right from the ground view as he maintains his spacing. I think you get the point!? Obviously cupping is less desirable for a Delta formation compared to a Diamond since it "shadows" Boss from the outer wing positions. Contrary to what the right wingman does, the left wingman typically flies more cupped in rolling maneuvers, given that Boss is continuously rolling into him (not a good idea to have a boot full on the rudder at that point when someone 3ft away is rolling his airplane at you).
Good points. In terms of toeing and cupping, as the WR are flying something in the middle of flat and stacked formation, for diamond rolls it's almost no toeing and all cupping, but for delta rolls outer wings use more toeing than cupping, since otherwise it is harder to fly for them and the delta looks awkward, like a 'cup' I'd say :D

The outer left wing in our case has to use some toeing too, because at some points of the roll he has his wings almost completely unloaded (near-zero G's), therefore banking becomes ineffective for lateral separation control.
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Post by Lawndart » Fri Jun 23, 2006 4:11 pm

Some examples of the Thunderbirds... (cough, cough)... screwing up. Note No. 6 (this year a left wing) getting wide and correcting back by "toeing". Also note how No. 2 is a little too wide, possibly being the culprit as to why No. 6 ended up "out", but got right back "in".
Image

In this shot the Diamond looks symmetrical and correct, flat formation with any toeing/cupping strategically masked from the crowd. Notice however, No. 6 (bottom) toeing into No. 2 and at the same time No. 5 (top of the roll) cupping into No. 3. All this happens so quickly in real life than by the time you spot it, they're already perfect again.
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I enjoy these shots, cause just as much as we know how it gives credibility to what we do online, it does in real life too. There's no such thing as a perfect show, but they do often come darn close and their technique of fixing errors is so good, most people don't even catch what was wrong in the first place. These men and women are some extremely skilled pilots making it look as easy as they do, but what most people don't know is the hundreds of hours of practicing and the countless of hours following each flight hours dedicated to detailed video review and evaluation. They may only fly 2 shows per week, but they spend 6 full days per week on the job with a lot of it being practice, critique and review in between the charity and recruiting work they also perform. Kudos to all those that do this day in and day out, for the enjoyment of "normal people" around the world!

LD
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Post by Lawndart » Tue Jun 27, 2006 9:29 pm

An even better illustration of "cupping"...

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Post by Viral » Fri Jul 21, 2006 3:37 am

Those last few shots of the Blues must have been from early in the practice season. Because both number 2 and 3 are off. There's some major cupping there on the right side of the diamond. And I'd imagine that 4 had to move down to avoid getting clipped by left wing in that lil' cup. heh
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Post by lqcorsa » Fri Jul 21, 2006 4:24 am

I'd imagine it has something to do with the turn rate of the outer aircraft being higher than the inside ones, or possibly it has something to do with speed.. Take marching for example. On a column left or right, the outside man/men on the outside do 2 45 degree angle turns while the inside man does one 90 angle one. Picture it, if to people walking side by side both did a 90 degree angle turn in the exact same direction, one or the other would end up right behind the turn leader.. Possibly same thing while flying. Maybe speed, and turn rate plays a factor in a similar form here?
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Post by Viral » Fri Jul 21, 2006 6:55 am

Yeah most def iqcorsa. And yeah i know all about speeds and turning rates in turns, i marched in a military style marching band and drum corp for 6 years. haha
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Post by lqcorsa » Fri Jul 21, 2006 6:32 pm

Viral wrote:Yeah most def iqcorsa.
Not sure why everybody thinks thats an i!!!!! Its Lqcorsa lol...


Yeah that was just my best guess. I notice while flying in formation with my squadron buddies I have to increase my thrust if I'm on the outsire of the turn...
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Post by Lawndart » Sat Jul 22, 2006 12:49 pm

There's much more to it than meets the eye. As told by the real #3 of the Thunderbirds from many years ago:

"When we start to roll I need to arc my way around the outside of Boss and therefore need to throttle up and pull back on the stick. I'm flying the biggest circle out of all the pilots in the Diamond. Initially I cannot put in too much rudder towards him, since it would destroy the look of the formation, but once we're sideways to the crowd and the roll rate has reached its max I use a lot of rudder into Boss. Then as we roll inverted I once again have to take out some of that rudder and align the nose with Boss'. Before we start pulling out of the bottom of the roll I once again use rudder as necessary when the profile view of the formation is seen from the crowd and hides the corrections I make. Finally we all have to take out the control deflections completely coordinated as we slow the roll rate down."

Don't quote me word for word on that. But this was the way a former #3 described his technique during a roll for the layman's in an interview several years back.

LD
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