Grafting a hardtop to an existing design is a popular option these days, given the popularity and practicality of hardtops in New Zealand's changeable weather. A hardtop greatly extends a boat's usability, allowing year-round boating if you're keen.
Challenger Boats have gone down the hardtop route with the 720HT. It has a raked stem (what the company calls "a long entry, monohedral hull form") and strake-less hull common to the whole Challenger range. The beam is carried well forward, offering volume inside the boat, and a variable deadrise flows into a moderate 18.5 - degrees at the transom. The chine rail runs almost parallel with the deck all the way to the bow.
The 720HT is a conventional fibreglass trailerboat in most respects. The hull's been around since the mid-1990s, but the decks have been modified to accept the hardtop, increase the cabin space and to accommodate a larger anchor locker with an automatic capstan.
Construction is strong, with hull and decks Plexus-bonded, then screwed and fibreglassed together, with sealed underfloor compartments providing strength, stiffness and buoyancy.
The layout of the review craft is influenced by its diesel engine installation, which is tidy and surprisingly unobtrusive. The Cummins Mercruiser 2.8-litre QSD turbo-charged, common-rail diesel produces 210hp at the propeller. It's a four-cyclinder unit that revs to a maximum of 3900rpm, with maximum torque at 2600rpm. The torque curve is relatively flat and particularly strong in the mid-range, where it's most useful.
It was this aspect of the boat's/engine's performance that was most impressive - for most of the review we had six adults on board but the load made little difference to the performance, with almost identical top speeds and little difference in acceleration whether we had six people in the boat or three
Draft: 3 ft. 2 in.
Beam: 8 ft. 1 in.
Standard features: 4 s/steel deck cleats
4 s/steel handrails
4 s/steel rod holders
4 internal rod holders
s/steel Navigation lights
2 Bilge pumps
215L under floor fuel tank
Freedom winch with warp, anchor and chain
Port/starboard side sliding window in cabin
Curved front windscreen
Recess for flush toilet
Coloured hulls offered (see separate sheet)
Large bait station/ski pole combination
Cockpit downlights (LED)
Cabin light (LED)
Cockpit lights (LED)
2 back to back seats
Upholstered trim panels on trays and cockpit
Sqabs and infill to front cabins (colour choice)
Weaver front hatch
Separate anchor locker
s/steel Bow roller
Reef Tornado carpet on floor (colour choice)
2 door battery locker
Under floor storage
Fleck 2 carpet in cabin & on cockpit walls
Fleck 2 carpet to cockpit roof
Double batteries and switch
12 volt power socket to cabin/cockpit
Trim tabs (auto return)
Full dashboard instrumentation (trip computer)