Sigma 38 Air Draft - anybody know?

[benw]

Have been searching for days to discover this but just can't find the answer.
Can anybody help with this one?
Many thanks.

 

[pvb]

Can't you scale it from the drawings?

 

[colingr]

Can you not work it out by measuring off a set distance from the mast, measuring the angle between the base and tip of the mast and using a bit of good old trig to calculate the height?


Height of mast = distance from mast * tan(angle)

 

[benw]

I am trying to keep this sensible but the boat is hundreds of miles away and the plans listed are not for a David Thomas designed/Marine Projects built Sigma 38.
Somebody out there must just know this surely?

 

[Koeketiene]

Have been searching for days to discover this but just can't find the answer.
Can anybody help with this one?
Many thanks.

According to this I is 15.85m.
Just need to add the height of the hull.

 

[colingr]

Ah, additional information not available when the previous answers were posted.

 

[pvb]

Ah, additional information not available when the previous answers were posted.

Usual story...

 

[colingr]

Right then

Get marina / boat yard / passing oik to photograph boat with an object of a known length in the picture.

Get him to email the picture to you.

Measure known object on photo and scale up to the mast height.

Job done.

 

[Quandary]

My Sigma 38 mast was 17.8m. (15.8m above deck) and since it was stepped on the keel it would be fairly close to the airdraft (not counting antennae)
If you need any more dimensions I have the Sigma 38 yearbooks etc. and can look them up for you.

 

[Koeketiene]

My Sigma 38 mast was 17.8m. (15.8m above deck) and since it was stepped on the keel it would be fairly close to the airdraft (not counting antennae)

No, no, no. Not helpful at all.
You need something either involving trigonometry or the plans of the wrong boat.

 

[colingr]

OK here's a Friday afternoon method.

Get a friend to train a swallow to carry a coconut up to the top of the mast. Get the swallow to drop the coconut and time how long it takes for the coconut to fall to sea level. knowing that the coconut with fall accelerating at 32 ft per sec per sec you can calculate the height.

More boring method would be to train another swallow to carry a coconut tied to a piece of string to the top of the mast. You can then simply measure the length of the string.

Or you could track down the author of this quiz

clicky

 

[benw]

Thanks Guapa.

 

[Quandary]

Thanks Guapa.

lakesailored ????

 

[colingr]

Thanks Guapa.

Guapa?

 

[pvb]

Guapa?

He means OR4751, who used to be Guapa before he fell out with the forum and left. But then he wanted to come back, so chose a different name, maybe to save face. Complicated things, forums.

 

[pvb]

http://www.ybw.com/forums/showthread.php?p=2973791

 

[Highndry]

OK here's a Friday afternoon method.

Get a friend to train a swallow to carry a coconut up to the top of the mast. Get the swallow to drop the coconut and time how long it takes for the coconut to fall to sea level. knowing that the coconut with fall accelerating at 32 ft per sec per sec you can calculate the height.

More boring method would be to train another swallow to carry a coconut tied to a piece of string to the top of the mast. You can then simply measure the length of the string.

Or you could track down the author of this quiz

clicky

This swallow? African or European?