english navigation astro

Wednesday, 24th of October

This morning, 3 protos have passed the equator. The wind will be a little bit lighter but Brian Thompson is still expected for Monday. The serial ranking is not really exact because the beacon of Jean Réhault,who was 2nd yesterday, didn't give a signal today. Electrical problems happens sometimes. Hervé was found in 9th position, but his likely to be 10th.

As you can see , problems can happen with the material.

So what happens if Herve looses his GPS? (Global Positioning system) or if his secondary GPS should not work?

Thankfully, Herve has attended an astronomical navigation course organised by the British mini- class (thank you once more Ian McKay).

The sextant is part of the compulsory equipment one must have on board the mini. That should allow him to have a relatively precise position of his latitude (position towards North) by doing sun meridian.

He will also know his longitude (position on the scale east-west) thanks to his watch only by calculating the difference between the time where the sun is at his maximum height locally and where it is at the maximum height in Greenwich (given by the navigation table).

But now lets imagine that Herve also looses his sextant. Is there a solution for him so that he can still go to Salvador de Bahia? During the astronomical navigation course, there was a section named: “Emergency astronomical navigation”. Herve learnt for example how to measure the angle between the horizon and the North Star without Sextant and how this angle represents more or less the latitude of the boat.

For more and more when he will not be able to see the North Star anymore, this would mean that he would be in the Southern hemisphere. He should just simply sail due West by looking at the sun and he should reach the Brazilian coast. This is a little bit basic but it is better than nothing.

Finally, lets hope that even if his old good ways of calculating your position are very practical, lets hope that they would not be useful for Herve! And he needs his GPS to find out where the equator exactly is to open the bottle of champagne given by his dad in Lanzarote!

	Hervé Favre website for the 2001 mini-transat

Hervé Favre website for the 2001 mini-transat

Wednesday, 24th of October

As you can see , problems can happen with the material.

So what happens if Herve looses his GPS? (Global Positioning system) or if his secondary GPS should not work?

Thankfully, Herve has attended an astronomical navigation course organised by the British mini- class (thank you once more Ian McKay).

The sextant is part of the compulsory equipment one must have on board the mini. That should allow him to have a relatively precise position of his latitude (position towards North) by doing sun meridian.

He will also know his longitude (position on the scale east-west) thanks to his watch only by calculating the difference between the time where the sun is at his maximum height locally and where it is at the maximum height in Greenwich (given by the navigation table).

For more and more when he will not be able to see the North Star anymore, this would mean that he would be in the Southern hemisphere. He should just simply sail due West by looking at the sun and he should reach the Brazilian coast. This is a little bit basic but it is better than nothing.

Finally, lets hope that even if his old good ways of calculating your position are very practical, lets hope that they would not be useful for Herve! And he needs his GPS to find out where the equator exactly is to open the bottle of champagne given by his dad in Lanzarote!