Calculating a turn?

[Guldager]

Hey

Just wondering if there is any way to calculate when to make a turn?

Let’s say i want to calculate when i should start a turn, i’m flying 400kts, and i have to turn 90 Degrees.
How far out from the steerpoint should i start turning? (this depends on the amount of G, yes i know)

Guldager

[Moort]

i suppose you could use wdp. it doesn’t tell you when to begin your turn however it calculates the turn radius for a given speed and altitude, which you could simply divide the amount of turn you wish to make to 360 and get a ballpark result.

otoh if it’s for IFR flying, like intercepting a radial for ex, then it has pretty straightforward way of calculating / formulae to find out when to begin your turn.

[Guest]

Neat trick I’ve learned… You use your mach number (I think this works but I might be missing a step)…

Mach number?

Yes! So you take your mach number, say .75 and subtract 20 from it, which nets you .55. You then move the decimal over 1 space to get 5.5. 5.5 away from the waypoint is when you start your turn and the turn should be a 30 degree bank turn I believe. (not degrees off your current heading, but with the bank indicator). I think that’s right. 15 or 30 but anyways, try it–worked for me the couple times I gave it a try.

There’s another guy in the 27th–Driscoll, he can probably better explain it than I can.

[Dee-Jay]

For IFR purpose (Arc DME in example) for a standard rate (180°/min) 90° turn you can use

D=TAS/200

i.e. … established inbound a TACAN station, you want to perform a TACAN ARC at 15 Nm … you are flying at 350Kts TAS …

Anticipation D = 350 / 200 = 1.75 … so around 2Nm

You will have to start your turn at: 15+2 = 17Nm inbound.

[Dee-Jay]

Yes! So you take your mach number, say .75 and subtract 20 from it, which nets you .55. You then move the decimal over 1 space to get 5.5. 5.5 away from the waypoint is when you start your turn and the turn should be a 30 degree bank turn I believe. (not degrees off your current heading, but with the bank indicator). I think that’s right. 15 or 30 but anyways, try it–worked for me the couple times I gave it a try.

Yep … good also! But Mach number work only at medium alt (from around FL100 to FL250)

[Guest]

@Mr_Blastman:

Mach number? say .75 and - 20 from it, which = .55 decimal over 1 space ‘.’-> to get 5.5. 5.5 away from the waypoint + 30 degree bank ± 15 or 30 * I think this works =

LOL, the Devil made me do it.:D

RAM22

[molnibalage]

@Mr_Blastman:

Neat trick I’ve learned… You use your mach number (I think this works but I might be missing a step)…

Mach number?

Yes! So you take your mach number, say .75 and subtract 20 from it, which nets you .55. You then move the decimal over 1 space to get 5.5. 5.5 away from the waypoint is when you start your turn and the turn should be a 30 degree bank turn I believe. (not degrees off your current heading, but with the bank indicator). I think that’s right. 15 or 30 but anyways, try it–worked for me the couple times I gave it a try.

There’s another guy in the 27th–Driscoll, he can probably better explain it than I can.

On which alt? Because on SL the M0.8 is close to corner speed, but at +25k M0.8 converting into CAS means, you even can’t perform a susatined 5G turn even in AA config with jammer pod…

IMHO the only way is pratice, practice, pratice. It does not work the “math in mind” during dogfigthing and missile evasion.

[Guest]

@RAM22:

LOL, the Devil made me do it.:D

RAM22

LOL

[Guldager]

@molnibalage:

On which alt? Because on SL the M0.8 is close to corner speed, but at +25k M0.8 converting into CAS means, you even can’t perform a susatined 5G turn even in AA config with jammer pod…

IMHO the only way is pratice, practice, pratice. It does not work the “math in mind” during dogfigthing and missile evasion.

I’m not talking about dogfighting or missile evasion
I’m talking about navigation between the steerpoints.

Thank you for the answers, i will try it out.
If you want to have a formula for all altitudes, i guess you would have to use groundspeed.

Guldager

[Dee-Jay]

@Guldager:

I’m not talking about dogfighting or missile evasion
I’m talking about navigation between the steerpoints.

Thank you for the answers, i will try it out.
If you want to have a formula for all altitudes, i guess you would have to use groundspeed.

Guldager

For nav between steerpoints, you don’t have to compute such things … just overfly or fly by the point no need to make it complex here.

[molnibalage]

@Guldager:

I’m not talking about dogfighting or missile evasion
I’m talking about navigation between the steerpoints.

Thank you for the answers, i will try it out.
If you want to have a formula for all altitudes, i guess you would have to use groundspeed.

Guldager

There is a very simple calculation formula in this manual.

http://www.mediafire.com/?jozwjuwigir

[-Pilgrim-]

When we did mission planning for F-4s and B-52s we had a whole series of turn radius templates . For current fighters (and Bones) it’s always planned point-to-point.

[Sting]

@RAM22:

LOL, the Devil made me do it.:D

RAM22

Just out of interest is there a thread on here that you haven’t posted in?? Fun is fun, but really to you have to add it to every single thread?? There is some great information on this forum, having to scan through these same post all the times is just frustrating to be honest.

Please don’t take offence, but I seriously think maybe some of this stuff needs to be limited.

Cheers

Sting

[Guest]

@Sting:

Just out of interest is there a thread on here that you have posted in??

Yes and No of course. There is the ignore function. I’d also like to make you aware I have posted more helpful information to the community then I’ve joked around for sure.;)

Make sure you give Everyone equal attention and reprimand them as well!!!

RAM22

[caper]

@Guldager:

I’m not talking about dogfighting or missile evasion
I’m talking about navigation between the steerpoints.

Thank you for the answers, i will try it out.
If you want to have a formula for all altitudes, i guess you would have to use groundspeed.

Guldager

About 5nm before reaching the STPT, select the next STPT check the Nav caret. It should be ahead of schedule. The trick is to start the turn early and adjust turn to put the flight on caret for the next STPT. It’s better to be early and select a heading off coarse (and maintain combat speed), let the caret catch up and make another turn to put the flight on coarse.

[Red Dog]

For navigation, I don’t calculate anything, I just turn when I feel it is needed.
Beside that depends if you’re on automatic or manual steerpoint. In auto, you need to almost overfly
It also depends on if you absolutely need to be on route? if you’re flying tactical formation (contract turn with your wing isn’t 30° turn ) etc etc
So many reason not to compute them.

In IFR, you have to compute the lead turns, especially from radial to arc and arc to radial. There are very easy formulae to use which are explained in the navigation tutorial
located in your \Docs\Airport Approach & Navigation Charts folder

[suhkoi69]

Radius = v²/(tan (60°)* 9.81) with units V (m/s) for 2G

[Blu3wolf]

@Red:

Beside that depends if you’re on automatic or manual steerpoint. In auto, you need to almost overfly

Its not meant to be that way… would be nice if this changed in 4.33

[thelawenforcer]

indeed, if these are the things you are concerned about, might aswell fly FSX or something

[Blu3wolf]

@suhkoi69:

Radius = v²/(tan (60°)* 9.81) with units V (m/s) for 2G

Y’know this is a pretty dead thread to dig up to post a formula on.