This Excel sheet calculates the required Bollard Pull to tow a conventional ship shaped vessel.
It rigorously calculates all the forces on the vessel, viz.
1. Calm Water Resistance: It is calculated using the established Holtrop and Mennen formula
2. Wind resistance: Based on Wind Height and Shape coefficients from ABS MODU rules, and corrected for wind direction.
3. Wave Resistance: From DNV Rules for Marine Operations, and corrected for forward vessel speed using Faltinsen, 1990
4. Propeller resistance and Hawser resistance: From US Navy Towing Manual
Useful in Marine Operations. It can be used to predict the bollard pull to tow a vessel. The tug can be accordingly selected.
Navaltik Portugal (verified owner) –
Saeed Khorram (verified owner) –
Hans Langsrud (verified owner) –
Lex van der Schaaf (verified owner) –
Works fine, little bit difficult to enter all parameters, as some unknown beforehand, outcome indications are however in line with reality.
Maybe useful to limit input a little bit, if possible and make the program more userfriendly.
m Lankford (verified owner) –
I have other product from The Naval Arch, that I have been using for the past 6 years, with ease of inputs it has assisted in my daily operations as a marine surveyor.
With all products there is full support, and updates
Jan Edeling (verified owner) –
Worked well, thank you
IGNACIO SANTANA (verified owner) –
Is a easy procedure for calculate the BP. user friendly.
Jonathon Pearce (verified owner) –
Excellent calculator but users need some knowledge on inputs which is good at academic level but not so much in practice.
Carl Henrik Frankman (verified owner) –
Especially the presented / calculated default values for certain input assisted with incomplete / unreliable information by the client. Here is also I see the greatest potential for improvement. Many of the coefficients can be estimated using thumb rules. Providing these would further enhance the programs usage, especially in a salvage context.
Team TheNavalArch (store manager) –
Thanks for the feedback Carl. We look to implement them in the next version