Bryan
When do you plan to incorporate aerodynamic jump in the Android app calculations?
Thanks
JCS
When do you plan to incorporate aerodynamic jump in the Android app calculations?
Thanks
JCS
DocUSMCRetired said:We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.
DocUSMCRetired said:We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.
BryanDocUSMCRetired said:We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.
DocUSMCRetired said:My apologies, but I do not have a release date for the next update at this time.
bigngreen said:I use Applied ballistics over all but if I'm concerned about jump I use Strelok pro, only app that I'm aware of that currently has it.
DocUSMCRetired said:All of our programs, except AB for Android has it. Including AB in iPhone. We are currently working on getting it integrated and running on the app at this time along with some other updates.
SierraCJ5 said:Please excuse my ignorance, but what is "aerodynamic jump"?
Bryan Litz said:There seems to be some confusion here on terminology.
Aerodynamic Jump (AJ) is usually discussed as being the vertical component of cross wind deflection. This is sometimes mistakenly referred to as crosswind jump. In a crosswind scenario, the aerodynamic jump is a systematic and predictable function of bullet stability and crosswind speed.
All mention of bullet imbalance and misalignment being related to dispersion is correct. However, the mechanism by which a bullet disperses from these things is called lateral throw-off. It's an inertial (mass properties) thing, not aerodynamic. So in the case of no crosswind, if you fire an imbalanced or 'off-axis' bullet, it will exhibit lateral throw-off at the muzzle which will establish some yaw. During the several precession cycles it takes to dampen the yaw is where AJ occurs as a result of the bullet being launched with some yaw rate.
So there are multiple ways for AJ to occur; either from the bullet entering a crosswind, or as a reaction to lateral throw-off in a random direction.
-Bryan
jcampbellsmith said:SierraCJ5 said:Please excuse my ignorance, but what is "aerodynamic jump"?
From another thread:
Bryan Litz said:There seems to be some confusion here on terminology.
Aerodynamic Jump (AJ) is usually discussed as being the vertical component of cross wind deflection. This is sometimes mistakenly referred to as crosswind jump. In a crosswind scenario, the aerodynamic jump is a systematic and predictable function of bullet stability and crosswind speed.
All mention of bullet imbalance and misalignment being related to dispersion is correct. However, the mechanism by which a bullet disperses from these things is called lateral throw-off. It's an inertial (mass properties) thing, not aerodynamic. So in the case of no crosswind, if you fire an imbalanced or 'off-axis' bullet, it will exhibit lateral throw-off at the muzzle which will establish some yaw. During the several precession cycles it takes to dampen the yaw is where AJ occurs as a result of the bullet being launched with some yaw rate.
So there are multiple ways for AJ to occur; either from the bullet entering a crosswind, or as a reaction to lateral throw-off in a random direction.
-Bryan
Regards
JCS
jim_k said:IN the field, if you don't have your app, just calculate the wind drift with the formula: [number of yard in 100's] x crosswind component in MPH, divided by the bullet's drift constant, usually 15 for a long-range bullet out to about 750 yards. So 4 x 15 divided by 15 is 4 MOA. Divide that by 10, and you get 0.4 MOA, which at 400 yards is about 1½ inches. There you go! This vertical effect causes bullet impact to be high if wind is from the right, and to be low if wind is from the left. Your wind is 3:00, so aim 1½ inches low. There's also an east-west coriolis effect, not much at 400 yards, but the app has it, if you enter direction of the shot. Impact high when shooting east, and low when shooting west. Of course, the usual spinning plate coriolis for northern hemisphere, maybe 1½-2 inches to rt of POA at 400. Don't leave home without your app.
DocUSMCRetired said:All of our programs, except AB for Android has it. Including AB in iPhone. We are currently working on getting it integrated and running on the app at this time along with some other updates.