What to buy? For North Sea rocket work

RocketDane · 27 July 2012, 19:35

Hi all

For a few years our rocket society has been picking up our launched rockets in the North Sea with our Zodiac Hurricane 4.8 meter RIB, but it really is too small with its 50 HP outboard. Now we are considering buying something more rugged but what?

A diesel inboard engine with lots of power would be nice and a length of 6-7 meters to be safe in the sea. But we need to tow it on the road and preferably to launch it directly from the beach. A jet drive might be useful to avoid damage to the screw.

I have thought about a Halmatic Pacific 22 but nothing is set in stone.

Any ideas?

Thank you in advance.

Jeppe Locht
Danish Space Challenge
Danish Space Challenge | Facebook

Pikey Dave · 27 July 2012, 19:43

What's your budget, you seem to be "aiming high"

RocketDane · 27 July 2012, 19:47

Quote:

Originally Posted by Pikey Dave

What's your budget, you seem to be "aiming high"

Sorry, forgot. Budget is as low as possible ;-)

We might be ready to spend up to 8-10 thousand pounds if the package was good enough, i.e. included instruments, a good trailer etc. We realize that we will not get anything flashy for that price but rugged is more important.

j.

Pikey Dave · 27 July 2012, 19:54

Quote:

Originally Posted by RocketDane

Sorry, forgot. Budget is as low as possible ;-)

We might be ready to spend up to 8-10 thousand pounds if the package was good enough, i.e. included instruments, a good trailer etc. We realize that we will not get anything flashy for that price but rugged is more important.

j.

Unless you are VERY lucky, I doubt that you will find anything in the inboard diesel/6-7m/jet drive/ reasonable condition range that will fit your budget. You either need to lower your spec or raise your budget by a factor of around 3

willk · 27 July 2012, 20:18

The move from Zodiac to Pac is a big step. Be aware that the Pac & Trailer is going to weigh well over 2.5 tonnes (I'm guessing this based on 1600kg for the basic Pac, 0.5 tonnes for the trailer and 0.5 tonnes of fuel and assorted crap)

Poly · 27 July 2012, 20:20

Quote:

Originally Posted by Pikey Dave

Unless you are VERY lucky, I doubt that you will find anything in the inboard diesel/6-7m/jet drive/ reasonable condition range that will fit your budget. You either need to lower your spec or raise your budget by a factor of around 3

Actually its not quite so ridiculous. This is a very well known PAC22 on here: http://www.rib.net/forum/f21/pacific...ono-47467.html that has an upgraded engine and modernised console. Whist this is a bit more original: http://www.rib.net/forum/f21/pacific...5-a-47725.html

A Pac won't give you great speed (even the 'uprated' ones struggle to get 30 knots) but will give you incredible sea keeping.

Probably not so easy with a jet drive - but unless you are usually working in very shallow water, or with people around you in the water or need incredible manoeuvrability its probably not worth the extra cost (in purchase or fuel). A depth finder and chart plotter would be a cheaper way of avoiding the bottom!

However with that budget I think you'd find it easier to get something with an outboard.

Pikey Dave · 27 July 2012, 20:34

Quote:

Originally Posted by Poly

Actually its not quite so ridiculous. This is a very well known PAC22 on here: http://www.rib.net/forum/f21/pacific...ono-47467.html that has an upgraded engine and modernised console. Whist this is a bit more original: http://www.rib.net/forum/f21/pacific...5-a-47725.html

A Pac won't give you great speed (even the 'uprated' ones struggle to get 30 knots) but will give you incredible sea keeping.

Probably not so easy with a jet drive - but unless you are usually working in very shallow water, or with people around you in the water or need incredible manoeuvrability its probably not worth the extra cost (in purchase or fuel). A depth finder and chart plotter would be a cheaper way of avoiding the bottom!

However with that budget I think you'd find it easier to get something with an outboard.

Fair do's

AND the price has dropped on Old Spice.

RocketDane · 27 July 2012, 20:45

1996 HALMATIC PACIFIC 22 EX MOD RIB WITH YANMAR DIESEL ENGINE | eBay
Halmatic Pacific 22 RIB & Trailer with 250hp Sabre Diesel and Hamilton Jet Drive | eBay

One of them is a JetDrive. Looks fine to me but then I am not a pro ;-)
j.

spartacus · 27 July 2012, 20:46

As Brucie would say "higher or lower?"

HALMATIC - FAFB

willk · 27 July 2012, 20:54

Quote:

Originally Posted by RocketDane

One of them is a JetDrive. Looks fine to me but then I am not a pro ;-)
j.

Hey "RocketDyne" - don't be fooled by the term "Jet", in this context it means 30% slower than plain old Prop driven

Poly · 28 July 2012, 01:01

Quote:

Originally Posted by RocketDane

1996 HALMATIC PACIFIC 22 EX MOD RIB WITH YANMAR DIESEL ENGINE | eBay
Halmatic Pacific 22 RIB & Trailer with 250hp Sabre Diesel and Hamilton Jet Drive | eBay

One of them is a JetDrive. Looks fine to me but then I am not a pro ;-)
j.

It's certainly not my area of expertise, but be wary of pac22s with jets. I am sure a knowledgeable person once told me that the earliest ones were retro fits on the standard hull and it handled very badly. Halmatic eventually engineered a modified hull (possibly the 24?) that overcame this. Of course I might be misrepresenting the situation, but I'd certainly be doing more investigating for a jet.

RocketDane · 08 August 2012, 07:14

OK, we have given up on the Pacific with Jet Drive and are currently thinking about an Osprey Falcon.

I have applied for money at several foundations and while I wait for the replies I have searched for more boats and stumbled over this FRC:
FRC til salg
It is a daughter ship of the Standby vessel Putford Sky
PUTFORD SKY - Vessel's Details and Current Position - 6607393 - 232003337
that has been scrapped.

The seller wants 30.000 GBP for it which almost puts it out of our economic range. On the other hand it is probably very safe? But on these pictures:
Putford Sky - IMO 6607393 - Callsign GWMA - ShipSpotting.com - Ship Photos and Ship Tracker
Putford Sky - IMO 6607393 - Callsign GWMA - ShipSpotting.com - Ship Photos and Ship Tracker
it seems to be low in the water and I don't feel like going out into the North Sea in it. What do you think?

I cannot find anything on the net about this boat or its builder.

best
Jeppe Locht

Cookee · 08 August 2012, 08:08

I thing you should look into what you can launch off a beach without a tractor first before even looking at boats.

Nasher · 08 August 2012, 08:15

Quote:

Originally Posted by RocketDane

engine with lots of power would be nice and - launch it directly from the beach. [/url]

It's a good looking and very Rugged boat, but I don't think you'll be launching it from a beach, and it will be VERY slow with 2 x 90HP.

Remember they will give you the equivalent power of @ a single 110HP, which on a boat of that size and weight may even struggle to plane with a few people on board.

Nasher.

RocketDane · 08 August 2012, 09:35

Quote:

Originally Posted by Nasher

It's a good looking and very Rugged boat, but I don't think you'll be launching it from a beach, and it will be VERY slow with 2 x 90HP.

Remember they will give you the equivalent power of @ a single 110HP, which on a boat of that size and weight may even struggle to plane with a few people on board.

Nasher.

I just got the specs from the seller. The boat was made by Watercraft International and they claim a speed of 28 knots light. I enclosed the specs FYI.

I like to have two engines for safety. Will a twin configuration really cost that much of the power?

best
j.

Nasher · 08 August 2012, 10:08

General opinion is that twins give equivalent 'performance' of a single of 60% of the total HP

ie twin 90hp = 180HP x 60%
or 108HP.

The last 1/4 throttle opening on outboards is where all the fuel is used. So 28knots flat out with twin outboards will use a lot of fuel for the performance, but will of course give greater safety.

For your use it's probably a good set up, as long as nobody wants to take it cruising as well.

Nasher

HughN · 08 August 2012, 10:11

Looking at some of the pictures of the rocket I found via Google, you are doing some very impressive stuff!

RocketDane · 08 August 2012, 10:21

Quote:

Originally Posted by HughN

Looking at some of the pictures of the rocket I found via Google, you are doing some very impressive stuff!

Thank you :-)

Our site is here: Danish Space Challenge | Facebook and you do not have to be a FB-member to look.

j.

RocketDane · 08 August 2012, 10:57

Quote:

Originally Posted by Nasher

General opinion is that twins give equivalent 'performance' of a single of 60% of the total HP

ie twin 90hp = 180HP x 60%
or 108HP.

The last 1/4 throttle opening on outboards is where all the fuel is used. So 28knots flat out with twin outboards will use a lot of fuel for the performance, but will of course give greater safety.

For your use it's probably a good set up, as long as nobody wants to take it cruising as well.

Nasher

I see your point. Hmmm. An inboard 200-250 HP diesel would be nice for this boat.
j.

willk · 08 August 2012, 11:14

Nasher has got his theory mixed up. The theory is that you "lose" about 50-60% of the SECOND engine's HP, not them both. It doesn't always work out quite as simple as that, but it's a good starting point.

He's quite right though when he says that the FRC will be horribly underpowered with twin 90s. It needs at least twin 150s to be any way useful, and even then, it's no rocketship.