# How are timed flybys executed, and what are their accuracy?

Thought experiment: Suppose I am equipped with an ideal automobile which can reach speeds of 700mph. On a highway, I can deftly maneuver around light traffic to achieve an average speed of 500mph. A friend, standing on an overpass, dares me to pass under him at high speed at a precise moment in time some distance in the future giving me enough time to reach my destination (if perhaps a bit early or late).

I would find this maddenly difficult. Likewise, aren't timed flybys difficult? How are they executed? Given an F16 with an average pilot, how accurate could a stadium flyby be timed? What technology is used?

Edit: Let be more specific. I. What are the exact procedures used by a flight team performing a timed stadium flyby. II. Given a highly trained team, what is the expected deviation from desired flyover team and actual flyover time?

I still don't think this question has been answered in detail. Also, there must be some technique that dates from the pre-GPS era. Even with GPS, I suspect (but I may be wrong) that the answer is more than staring at a GPS and intuiting the appropriate adjustment in speed.

• See for example youtu.be/_dTmrSI0bts?t=19. Presumably there is an agreement that the planes should reach the stadium just as the national anthem is ending. Jul 26, 2015 at 7:45
• Driving an aircraft can be extremely accurate. You can fly legs of precisely known length at precise speed with the only variable being wind. With an up to date forecast and a small amount of time to allow for errors, it is easy to arrive on time. The Red Arrows will arrive a little early, do a circuit or two a few miles away with an exact time to run into the show and therefore, be able to arrive to the second. Jul 26, 2015 at 9:40
• All you need is something that gives you precise distance to waypoint and preferably calculated time to waypoint using your current speed. Even a basic GPS module can do that. Jul 27, 2015 at 6:42

The way they coordinate them is actually extremely simple. The show at a ball game (or any major event) is usually very heavily choreographed, so they know exactly when it's going to end (seriously, often down to the exact second. They practice the heck out of those things.) So, step number one, the organizers tell the Military the exact time for the flyover in the show.

For the militaries part, well, it's important to remember that military aviation involves a lot of instances where you have to be over a target, dropping a munition, at an extremely precise time (again, down to the second). Otherwise you may screw up the timing of the whole operation, or the target may be gone, or the defenses may be up (etc etc). It's really important to be precise in the military.

The procedure itself is still fairly conventional though. You figure out what time you need to be there, then you figure out how much time it will take you to get there. Subtract the latter from the former and boom, you have the time you need to take off. Then all they need is a few check points to make sure they are on schedule, approaching at the proper speed. And they adjust as needs be.

Basically, keep an eye on the clock, slow down if you're ahead of schedule, speed up if you're behind. To increase accuracy, you may build in a holding spot near the event, that way if you're 20 minutes early (of if the planning goes out the window for the show and they're late...), you can hold there and pick the approach up again when the time is right. It's still all about watching the speed and the clock though. With a lot of practice, you end up hitting your waypoints, hold points and destination, with (literal) military precision.

If you want to know more details though, check out this article from ESPN: How Flyovers Hit Their Exact Marks at Games.

As a final thought, I think you may need to adjust your thought experiment. Military aircraft can get clearance through just about any airspace prior to the actual mission. Plus, they can approach from any direction, so it's pretty easy to find a lane that has no traffic. So in your car thought experiment, there should have been no traffic and a straight shot to the overpass.

Plus, there should have been regular beacons (like GPS or NDB fixes) to tell you how far you are from that overpass. And the person driving the car would have known exactly what time they needed to pass each beacon in order to get to the overpass in time. Then, with a heck of a lot of practice, I'm sure that driver could go under that underpass at the exact right moment pretty much every single time...

• "military aviation involves a lot of instances where you have to be over a target, dropping a munition, at an extremely precise time (again, down to the second)" Is that really true? Wouldn't that require predicting the enemy's actions to the nearest second, too? Aug 6, 2015 at 22:05
• @DavidRicherby I may have gotten a little overly excited with the word "extreme", but the article backs me up on the idea that military pilots are trained to be precise enough to be within a second or two at least. I think you may have to pester RhinoDriver if you want real world examples of why that would be the case. Aug 6, 2015 at 22:52

A friend of mine did ATC for Camp Atterbury in Indiana. He used to coordinate the fly-by for the Indianapolis 500. I believe the fly-by would be timed for the end of the National Anthem (though, this being Indiana, it might have been at the end of Back Home Again in Indiana).

They, of course, had an official schedule and knew when the song should finish. However, variations were always possible, and were expected. He was stationed at the track listening to the song, and had a radio to communicate with the pilots of whatever was flying by. They would know when they should be on target, but he would give them a more accurate count-down to ensure they arrived as close to the end of the song as possible.