Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors
Old 08-09-2011, 12:14 AM
AnneY AnneY is offline
Junior Member
Join Date: Aug 2011
Rep: 10 Posts: 6
Location: Philippines
HELIPAD for yatch retrofit


Good day!

I am an engineer currently involve in a naval ship conversion project. We are currently considering the addition of an helipad to the retrofit of the naval ship to a yacht but research is necessarily to verify if this is possible. As a part of our research, we are trying to find information regarding the rotor clearance/deck clearance required for different size and model of helicopters, particularly twin engines helicopters that can accommodate 5-7 passengers.

If there is any information you can give us or at least point us to the right direction, you can reach us through this email.
Any assistance from you will be greatly appreciated.

Anne Yumul
Civil Engineer
Reply With Quote
Old 08-09-2011, 12:53 AM
Frosty Frosty is offline
Previous Member
I might suggest your on the wrong Forum. Theres are guys here will gladly advise you but after being here for donkeys years I know not of one that has helicopter experience.

I noticed your a civil engineer and not naval nor did you include your email as you said you had. If I/ we are to accept you question as credible... well some things don't kinda add up.

Perhaps contacting the helicopter manufacturer for rotor clearance, but living in a marina with a few helicopter clad vessels they don't normally fly them right up to the final position. Im sure the pilots will explain "walk"

Some ostentatious owners squeeze on helicopters that should not be there. The tip to boat fixture is critical.

This distance is refered to as "F" as in 1 meter tip clearance would be F'n close.
Reply With Quote
Old 08-09-2011, 01:11 AM
Ad Hoc Ad Hoc is offline
Naval Architect
Join Date: Oct 2008
Rep: 2488 Posts: 5,203
Location: Japan
Originally Posted by AnneY View Post
If there is any information you can give us or at least point us to the right direction, you can reach us through this email.
Any assistance from you will be greatly appreciated.
All you need to know, for now at least, is in CAP 437. (google it)
Reply With Quote
Old 08-09-2011, 01:41 AM
AnneY AnneY is offline
Junior Member
Join Date: Aug 2011
Rep: 10 Posts: 6
Location: Philippines
Thank you for the responses.
If this would be of any use, this is my email address:

I am working for a private company whose owner bought a naval ship and wants to convert it to a private yacht. I know I am a civil engineer and no where knowledgeable about naval architecture but as what all employees need to do, I need to accomplish anything my employer asks me to do. And one of the task assigned to me was to research about boat retrofits.

I joined this forum in the hopes of gaining knowledge or at least being more familiar with boat architecture and other topic related through posting and forum discussion.
Reply With Quote
Old 08-09-2011, 01:45 AM
Ad Hoc Ad Hoc is offline
Naval Architect
Join Date: Oct 2008
Rep: 2488 Posts: 5,203
Location: Japan

Well, i hope your client has lots and lots of money and plenty of patience!

Where abouts in Phili are you doing the converstion?

(I used to work in Phili).
Reply With Quote
Old 08-09-2011, 01:48 AM
Frosty Frosty is offline
Previous Member
Clarke air base probably down Feilds Avenue. Now don't tell me you don't know where that is.
Reply With Quote
Old 08-09-2011, 01:54 AM
AnneY AnneY is offline
Junior Member
Join Date: Aug 2011
Rep: 10 Posts: 6
Location: Philippines
I know Clark Air Base. Actually I live just one town away from Clark.

The naval ship is now docked at Bataan and is currently undergoing testing and inspection.
Reply With Quote
Old 08-09-2011, 02:20 AM
Frosty Frosty is offline
Previous Member
Yes I know it well too, I know lots of chrome pole polishers.
Reply With Quote
Old 08-10-2011, 03:01 PM
ABoatGuy ABoatGuy is offline
Join Date: Aug 2004
Rep: 79 Posts: 206
Location: LeftCoast
The LY2 rules have a section on helicopters. Rule is for commercial yachts in the UK, but good reference for others.
Reply With Quote
Old 08-10-2011, 03:06 PM
Stumble Stumble is offline
Senior Member
Join Date: Oct 2008
Rep: 739 Posts: 1,884
Location: New Orleans

You might want to contact the builder of the vessel. A lot of navy ships do have helicopter capability in some configurations but not others. It is possible that they already have a design brief to have a helipad as an option.

Can you give the class of vessel, and navy it's from? This might help a lot. Some of the researchers here are a living breathing knowledge base of all things nautical.
Greg Rubin
Captain-Attorney-Boat addict
Reply With Quote
Old 08-10-2011, 04:52 PM
JosephT's Avatar
JosephT JosephT is offline
Senior Member
Join Date: Jun 2009
Rep: 218 Posts: 474
Location: Roaring Forties
As an aeronautical engineer and former member of US Marines helo squadrons (we operate helos on flight decks), there several factors to consider:

1. Ship design: Need more info on this ship to comment. Unless the ship design allows such a retrofit this could be a very risky modification to say the least.

2. Helo specs: Need more info on the helo moke/model (e.g. weight). Most sea based helicopters are built from the ground up for sea conditions. All aluminum arts are treated (e.g. alodine), primed and painted to ensure minimal corrosion. Otherwise, the aircraft structure and systems will surely corrode which leads to malfunctions and safety issues.

3. Excellent training: Ships move so much training is needed to locate the moving boat and land on it while under way in good or bad weather. Generally, flight ops are halted in bad weather. Also, all flight crews should be excellent swimmers and ideally be life guard certified (comes in handy when rescuing passengers if pilots need to set helo down in the water).

4. Maintenance shop: Aside from the landing pad, the yacht should have a workshop and space to store spare parts. If the helo is to be operated at sea for any given period of time it will need this type of support.

5. Fresh water spray down: At the end of each day the helo should receive a fresh water spray down on deck to rinse salt from all helo parts (skins, flight control actuators, engines, etc. Again, most helos operating at sea are built for such operations. They include water ports to connect fresh water hose to make engine wash down easy.

6. Obstacles on deck: On deck, generally speaking helo rotor blades should have 3x spacing from vertical obstacles on the ship (e.g. ship tower). This generally allows safe operation. Pilot skills are also critical. Any pilot operating on a ship should be well trained to land on a small, moving landing pad. I would suggest you dialogue with Phillipine Navy pilots. Most likely the owner will hire one of them to fly crew.

This is no doubt a major modification to a ship. Be sure to do all your homework or lives will be lost. Even with ideal conditions operating a helo on deck if a ship is very risky.
Reply With Quote
Old 08-10-2011, 06:52 PM
AnneY AnneY is offline
Junior Member
Join Date: Aug 2011
Rep: 10 Posts: 6
Location: Philippines
Good day.

Thank you for your responses.
I will forward them to my superior.
As for the class of the navy ship, we were not given the full specs of the ship for confidentiality reasons.
All we know is it is one of the seven vessels of the British Royal Navy have been named HMS Bulldog.
Reply With Quote
Old 08-10-2011, 08:42 PM
Frosty Frosty is offline
Previous Member
Bulldog class survey vessel
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Class overview
Name: Bulldog class coastal survey vessel
Builders: Brooke Marine, Lowestoft
Operators: Royal Navy
Preceded by: Hecla-class survey vessel
Succeeded by: Echo-class survey ship
Built: 1967–1968
In commission: 1968–2002
Completed: 4
Retired: 4
General characteristics
Type: survey vessel
Displacement: 1,050 long tons (1,067 t)
Length: 189 ft 6 in (57.76 m)
Beam: 37 ft 5 in (11.40 m)
Draught: 12 ft (3.7 m)
Propulsion: 4 x Lister Blackstone diesel engines
660 bhp each
2 x shafts
Speed: 15 knots (17 mph; 28 km/h)
Range: 4,000 nautical miles (7,400 km) at 12 knots (14 mph; 22 km/h)
Boats and landing
craft carried: 2 × 9.5 m survey boats
Complement: 4 officers
34 ratings
Sensors and
processing systems: 1 × 1007
Armament: None (fitted for 2 x 20 mm Oerlikon GP)

The Bulldog class was a four ship class of survey vessel in service with the Royal Navy from the late 1960s until the start of the 21st century. Initially designed with service overseas in mind, they spent most of their careers off the British coast. A fifth ship was subsequently built to a modified design to support them in their activities. Decommissioned and sold off at the end of the 20th and start of the 21st centuries, they have continued in service as civilian vessels, with some being converted to private yachts and others entering other commercial sectors.

* 1 Design
* 2 Careers
* 3 Ships
* 4 Notes
* 5 References

[edit] Design

The Bulldogs were designated as coastal survey vessels, and were a variant of the earlier Hecla-class designs.[1] All four ships were built by Brooke Marine utilising merchant hulls.[1] The resulting design was stable in a variety of sea conditions, and the class was considered to be good seakeepers, with an all-welded construction, a bulbous bow and a high flared forecastle.[1] Anti-rolling tanks and twin rudders were also fitted. The ships used eight-cylinder diesel engines powering two propellers and were fitted with specialised echo-sounders, Marconi Hydrosearch sector scanning sonar and a variety of sonar and radar. In addition they carried two small surveying boats, fitted with echo sounders.[1]
[edit] Careers

They were intended to serve overseas in pairs, with four ships being ordered in the late 1960s: Bulldog and Beagle; Fawn and Fox.[1] Despite the original intention to use them overseas, the growth of the exploitation of the oil and gas reserves in the North Sea from the 1960s onwards led to them spending most of their time engaged in survey work off the British coast.[1] The increased demand for their services led to the Admiralty ordering a fifth ship to a modified design in the 1980s, which became HMS Roebuck.[1]

Fox was the first of the class to leave service, being sold to commercial interests in April 1989.[2] Fawn was paid off in October 1991 and sold to interests in West Germany to become an offshore support vessel of the West African coast, and the China Sea under the name Red Fulmar.[3] Bulldog was paid off on 26 July 2001 and sold the following month for conversion to a luxury yacht. A major fire broke out while she was moored at Nelson, New Zealand and the conversion was not completed.[4] Beagle was the last to leave service. She was paid off on 7 February 2002 and sold the following month to a yacht company at Poole for conversion.[5]
[edit] Ships
Name Pennant Launched Completed Commissioned Fate
Bulldog A317 12 July 1967 1968 21 March 1968 Paid off on 26 July 2001
Beagle A319 7 September 1967 1968 9 May 1968 Paid off on 7 February 2002
Fawn A325 29 February 1968 10 September 1968 4 October 1968 Paid off in October 1991
Fox A320 6 November 1967 1968 11 July 1968 Sold in April 1989
[edit] Notes
Reply With Quote
Old 08-10-2011, 10:24 PM
masalai masalai is offline
Join Date: Oct 2007
Rep: 1882 Posts: 6,847
Location: cruising, Australia

In the 1960's the need to update the Royal Navy hydrographic flotilla was officially recognised and three new Ocean Survey Ships to replace the aging Scott and Shackleton were envisaged. The three Ocean Survey ships were ordered, built and named Hecla, Hydra and Hecate. In November 1971 a fourth and improved vessel, named Herald, was ordered from Robb Caledon shipbuilders to replace the elderly survey ship Vidal.
The hull design was based on that of Discovery, a Royal Research Ship, and the Hecla class were built to commercial standards costing £1.25 million each. To help with hydrographic tasks each vessel carried two small survey craft, a launch, a land rover and a Wasp helicopter for which there was a flight deck and hanger. All four vessels had a displacement of 2,733 tons and a length of around 80 metres. Powered by Paxman Ventura diesel electric engines they had a speed of 14 knots. Bow thrusters and stablaisers gave the ships good seakeeping abilities and maneuverability. All four ships had a complement of around 118 with the commanding officer usually holding the rank of commander.
Maybe the original did not have a helicopter capability, hence the change noted in BOLD, for their replacement on decommissioning...
Try to be helpful...
Remember that there are at least two sides for every story...
Reply With Quote

Old 08-10-2011, 10:32 PM
AnneY AnneY is offline
Junior Member
Join Date: Aug 2011
Rep: 10 Posts: 6
Location: Philippines
We are currently confirming the helicopter model the owner wants to land in the yacht. With the helicopter model identified, hopefully we will be able to research for its specs. Most probably it will be a twin engine Bell model that can house more than 5 passengers excluding the pilot.

I was also able to research about retractable helipad that can be custom fitted to a yacht. Headland is the name of the company. But this might be a expensive option considering there is a need to outsource a designer/consultant for the fitting.
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
retrofit jet drive autobahnbuyer Jet Drives 3 03-08-2010
11:11 PM 
Helipad material 902twin Boatbuilding 6 06-07-2007
04:48 PM 
yatch design schools??? samsingh17 Boat Design 5 05-24-2007
02:52 PM 
Retrofit turbine engine to powerboat. Verytricky Propulsion 21 02-24-2006
01:54 PM 

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.

All times are GMT -5. The time now is 06:51 PM.

Powered by: vBulletin Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2017 Boat Design Net