TWA bug

Want to report a bug? Any questions? Post them here to get help.

Modérateurs : Admin bis, Admin anglais

Avatar de l’utilisateur
limelight
Joueur
Messages : 749
Inscription : 22 août 2019 10:15
Localisation : Melbourne, Australia
Contact :

TWA bug

Message par limelight » 31 mars 2020 20:06

On the fast fastnet race, I've hit a strange bug:

Wind is 19.4 k / 58°

Program point 5 has set a heading of 104°, by my reckoning this makes TWA 46 (46+58 = 104)
but the programmer insists it is 35???
Image
Check https://madinstro.net/rg/ for handy navigation tools.

Benoitsuomi60
Joueur
Messages : 422
Inscription : 24 mai 2015 18:32
Contact :

Re: TWA bug

Message par Benoitsuomi60 » 31 mars 2020 21:25

121 - 76 = 45
104 - 69 = 35 :!: :shock:
You got it :?: :!: ;)

It's not Now, it's + 12H :lol: :lol:

Avatar de l’utilisateur
limelight
Joueur
Messages : 749
Inscription : 22 août 2019 10:15
Localisation : Melbourne, Australia
Contact :

Re: TWA bug

Message par limelight » 31 mars 2020 23:45

You must be right... but I was sure it was after the weather update. I waited for it on JV because it took so long to get the green... or so I thought. But you're right Prog 1 is at 19:54 so it's not yet the 'new' wind and I should be +12. Stupid me :lol:

This new time is such a pain and worse will come when we switch to winter time, the weather update will be at 3am and I'll need to get up at least 30 minutes before to do any sensible programming.

I'll stick to the team challenge since I've committed to it... but that's it. No more races for me till next Summer.
Check https://madinstro.net/rg/ for handy navigation tools.

Avatar de l’utilisateur
limelight
Joueur
Messages : 749
Inscription : 22 août 2019 10:15
Localisation : Melbourne, Australia
Contact :

Re: TWA bug

Message par limelight » 14 oct. 2020 21:30

To whom it may concern:
I've identified a minor bug in RG's polar display after the recent modifications. I have reported it in the French forum but I want to make sure we English speakers are aware of it. The red TWA angle indicating best VMG is not always correct, so far the bug is the TWA when running, the close hauled one seems to agree with my calculators.

The differences in VMG are small, of the order of 0.01 knot, but every little bit helps so you may want to calculate the VMGs yourself and pick the corret TWA... or use my calculators.

Cheers,

John
Check https://madinstro.net/rg/ for handy navigation tools.

Avatar de l’utilisateur
limelight
Joueur
Messages : 749
Inscription : 22 août 2019 10:15
Localisation : Melbourne, Australia
Contact :

Re: TWA bug

Message par limelight » 27 oct. 2020 00:13

There is still a little bug in RG's polars:

Image

RG show 145 in red as the TWA giving the best VMG, but I find 142 is better:

With 145:
VMG = - 15.90 * cosine(145) = 12.9505 knots

With 142:
VMG = - 16.57 * cosine(142) = 12.9776 knots

Therefore 142 is clearly better, until this bug is fixed you had better do a hand check yourselves. RG's value is never far but is not always the best.
On the other hand, when going against the wind, I haven't found any dicrepancy yet.
Check https://madinstro.net/rg/ for handy navigation tools.

Avatar de l’utilisateur
blzblz
développeur
Messages : 3212
Inscription : 16 oct. 2014 21:05
Contact :

Re: TWA bug

Message par blzblz » 27 oct. 2020 08:45

Hi limemight,

The VMG display has been fixed on the polar diagram and table, on the main interface and on the popup window.
Could you check with your calculation tool wether it is now ok or still not ok, please ?
Thanks in advance ;)

Avatar de l’utilisateur
limelight
Joueur
Messages : 749
Inscription : 22 août 2019 10:15
Localisation : Melbourne, Australia
Contact :

Re: TWA bug

Message par limelight » 27 oct. 2020 11:29

Hi Blaise,

I checked with the Multi 50 med 18, and I now have perfect agreement between RG's polar diagram and my calculator.

Tomorrow I'll check a few different polars, but I think you fixed the problem.

Thanks,

John
Check https://madinstro.net/rg/ for handy navigation tools.

Répondre

Revenir à « Bugs & FAQs »

Qui est en ligne ?

Utilisateurs parcourant ce forum : Aucun utilisateur inscrit et 3 invités