Firebar

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About Firebar

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    The Solent

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  1. Firebar

    USS Lexington CV-2 discovered after 76 years

    The legend of the Swordfish attacking the Bismark says that they were flying slower than the anti-aircraft batteries could be trained to...
  2. Firebar

    VOR Leg 4 Melbourne to Honkers

    It was a MS10 airborne liferaft, standard fit on the RAF transport fleet, they’re pretty typical of what you’d see in a commercial raft. The raft may weigh hundreds of kilos but the helicopter weighs thousands. The downdraft can get underneath and flip them, it’s more common with the bigger aircraft, the AW101/Merlin has a particular problem from a high disc loading, but on this occasion it was an AW189. There’s a Defence Aviation Safety Occurence Report about somewhere about the Merlin flipping a raft in training.
  3. Firebar

    VOR Leg 4 Melbourne to Honkers

    I was surprised to see the raft, they’re incredibly unstable when light with a helo downdraft. I’ve been in a 10 man with 3 people in it that nearly capsized when the whichman was in the door (training exercise). I would have thought that a hi-line would be the favoured option, unless they weren’t clear on the state of the damage to the boat.
  4. Firebar

    J/112E

    Try contacting Paul Heys via Key Yachting, they’re the UK J dealer and from what I remember he was out on Davanti regularly. http://www.keyyachting.com/
  5. Firebar

    Rules Question - OCS

    This is how the Round the Island Race handles OCS. 10.1.2 RRS Appendix A4.2 is changed in that a boat that remains OCS will be scored with a time penalty of 5% of the boat’s elapsed time rounded to the nearest second, unless the Race Committee decides that the boat has gained a significant advantage in the Race, in which case she will be scored as OCS. The phrase significant advantage leaves it to the discretion of the committee, and the penalty is low to try and get those who might not race often to not try to go back in the face of the next 100 boat start with 1000 boats waiting
  6. Firebar

    AIS to iPad or other tablet

    Check the manual on the specific AIS unit for this, NMEA0183 is technically an RS422 signal but some older units actually output a RS232 signal. Some newer units are compatible with both. If the one you're looking at can do RS232 the converters are often cheaper as it's more common. Electrically the difference is that RS232 has a signal and a ground wire for transmit and receive (often a common ground, I.e. 3 wires) and RS422 is a differential signal (a +ve and a -ve for transmit and receive so always 4 wire). The good news is that when you read the manuals on most ais units they're compatible with RS232 and RS422 because they tend to have been used interchangeably over the history of NMEA0183.
  7. Firebar

    AIS to iPad or other tablet

    It's not too bad. You can buy a RS232 to USB Ccoverter quite cheaply, just plug it in, run the pi off a 12v to USB socket, install kplex with 1 command, set up the dongle (admittedly more complex but lots of tutorials) and set kplex to run on startup. Maybe a couple of hours of following tutorials.
  8. Firebar

    AIS to iPad or other tablet

    For a cheap wifi option how about NMEA0183 via RS232 to USB plugged into a raspberry pi running kplex with a wifi dongle plugged into it to get it onto NMEA over IP.
  9. Firebar

    Race tracking

    AIS comes in a couple of types, Class A Transponders are for commercial vessels and are very expensive. For a yacht you'd either get a receiver or a Class B transponder. The receiver only gets other people's signals and the transponder will transmit yours and recieve too. Class B tend to transmit Position, SOG, COG, MMSI, Callsign, Vessel Name, Vessel Type only, Class A will transmit loads of info. They need a link to a GPS (most have internal ones and just need an antenna) and a VHF antenna, some have inbuilt splitters so you can plug your main antenna into them and then to the radio from them. Others need either an external splitter or a seperate VHF antenna, RORC specifies that your AIS system must use the masthead antenna, so our system has a splitter. If you want to view the output you need a laptop, a chart plotter, or to have it linked to WiFi to receive on a tablet. Range is normal VHF, but masthead to masthead it can be significant, I picked up a target at over 100nm on a race recently, but that was unusual. The way the system actually works is like a datalink, the Class A units set up a transmission pattern, repeating over about a minute or so. A Class B set will listen, find a blank spot and attempt to transmit when it arrives again, if it fails it will look for another slot, so Class B transmission frequency is lower than Class A. The actual transmission is a compressed message that requires further translation. Cost wise they're certainly cheaper than they were but certainly still in the hundreds of dollars/pounds.
  10. Firebar

    Race tracking

    I like tracking, especially to compare tactics post race. RORC did some AIS/Satellite tracking this year, it worked pretty well. A few boats had satellite transmitters that sent the AIS feed from their systems back to Yellowbrick. Mind you it only works as RORC requires AIS transponders.
  11. Firebar

    2017 Rolex Fastnet Race

    RORC are billing it as the largest offshore race in history in the press releases at the moment. I guess as they own IRC they're a bit less focused on line honours and the big boats and more on handicap winner than some other races.
  12. Firebar

    IRC Rating Impacts

    Well that was an exceedingly wet Channel Race! 50 nm upwind in 20 kts to close enough to Cherbourg that you can almost taste the steak and then turn around and go to Eastbourne on a 75 nm downwind with the wind dropping to 10 kts then a finish back into 20 kts into the Solent. It was the first time that I have used a "box" mark. All you had to do was provide evidence of a fix in the box but you could enter and leave from any direction, which with people taking differing tidal strategies meant that it all got a little exciting in the dark. I was aware of the extra kite rule (11.2 in IRC) but it says only at the prescription of the rating authority. From what I can see in the NOR and SIs there is no prescription altering that rule for RORC Offshore Races, unless I'm missing something entirely! The only races I could find the prescription for are the Transat and the Hamburg-Bermuda Race. I would say that that J/109 is rating with an overlapping #2 headsail, that is about what the UK boats with a #2 rate as, when you start optimising for IRC I've seen ratings (on French boats) under 1.000, but most common seems to be in the 1.006 - 1.010 range, mostly depending on if the boat has been measured I think. Our set up is class standard except for the headsails, which are slightly larger than a class #3. I don't fancy playing with the JPKs that much! We did that a couple of years back on the Sigma 38 and that was tough then and they've only got better since! IRC 3 is where we get the most level racing really, as all the other J/109s are in there, and the boats are all so close that it's good fun trying to sneak past each other all the time!
  13. Firebar

    IRC Rating Impacts

    We managed to get the extra spinnaker and a slightly larger spinnaker into the committee early enough that they have issued us with another new certificate for 1.004 and have agreed to let us race the Channel Race with it tomorrow. RORC really have been very helpful in getting it all sorted out, though we show with the wrong number on the entry list it's that last minute!
  14. Firebar

    IRC Rating Impacts

    That's what happens when you've got a 14 year old boat that's not been weighed and is using the manufacturers light boat displacement as a non-endorsed weight I guess! General wisdom does say be the fastest in your class, but it's also nice to race against boats of the same type and all the other J/109s are in IRC3 and that's where we've been all season.
  15. Firebar

    IRC Rating Impacts

    We came out 400kg heavier than the non endorsed weight for starters. The cert numbers look about right on the dimensions.