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Ranger Tugs · Current Production · Trailerable diesel cruising tug / compact trawler

Ranger Tugs R-31

A diesel inboard Ranger Tug for captains who want more cruising boat than the R-27 without leaving the trailerable-tug idea behind. The R-31 is a compact extended-cruising platform with two sleeping cabins, one enclosed head plus day-head functionality, real cockpit utility, and a choice between Sedan simplicity and Command Bridge outdoor helm life.

The Ranger Tug R-31 is for the captain who likes the Ranger idea but wants a more complete cruising envelope than the smaller outboard boats provide. It is still compact and trailer-minded, but the 10-foot beam, Volvo diesel, two sleeping cabins, larger cockpit, and available Command Bridge move it into a different kind of cruising life. On the Loop, it is best read as a couple's diesel tug that can host, fish, day-run, and cruise for weeks — but whose trailerability and bridge profile require more nuance than the smaller Rangers.

Design Intent

Ranger Tugs appears to position the R-31 as the extended-cruising member of the small-tug family. The builder describes it as sharing many features with smaller sisterships while adding the volume, cockpit, foredeck seating, stateroom arrangement, and cruising equipment that make longer trips more practical.

The boat's intent is clearest in the split between R-31 S and R-31 CB. The Sedan keeps the profile simpler and lower, with a published 13'10" mast-up bridge clearance. The Command Bridge adds an upper helm, full controls, seating, and outdoor social space, while raising mast-up clearance to 18'2". That changes the way the boat lives and the way it fits the route.

The R-31 also sits at an interesting point in Ranger's philosophy. It remains trailerable in the builder's language, but at 10 feet of beam it asks owners to treat trailering as a planned operation rather than casual driveway geography. A forward island berth, midship stateroom, convertible dinette, helm-side door, bow and stern thrusters, and standard Volvo D4 diesel all point toward a couple who wants a compact cruising boat that can be handled without crew but still feels substantial for extended waterway travel.

The Numbers That Matter
34'10"loa · rigged
Meaningfully larger than the pocket Rangers but still compact for transient slips, locks, and couple-handling.
10'0"VERIFYbeam
More interior and cockpit comfort than legal-width trailerables; trailering becomes an oversize-width exercise.
30"VERIFYdraft
Excellent for the Loop; keeps shallow-water pressure low across the ICW, inland rivers, marina entrances.
13'10"VERIFYair draft · R-31 S mast up
Clears the 19'6" Loop limit with comfortable margin.
18'2"VERIFYair draft · R-31 CB bridge & mast up
Under the 19'6" Loop limit on paper but deserves measured confirmation — about 16" margin before accounting for load, gear, and antennas.
180 galfuel · diesel
Useful tankage; official performance table suggests efficient low-speed range and 15–16 kt cruise capability.
2staterooms
Real forward cabin plus midship berth distinguishes the R-31 from smaller pocket Rangers.
Air Draft → Bridges
19'6" CHICAGO FIXED-BRIDGE LIMIT1' marginR-31 S: 10'0" mast down / 13'10" mast up; R-31 CB: 10'3" bridge & mast down / 18'2" bridge & mast up
Mast-up, she clears the route's governing bridge — but with about a foot to spare. Lower configurations open that gap considerably.
Draft → Shoaling
WATERLINEtypical ICW thin-water band30"
Her keel rides well clear of the band that worries deeper boats — comfortable margin through most of the ICW and the rivers.
Beam → Locks & Slips
LOCK CHAMBER ~50–110'10'0" beam
Substantial but not excessive in a lock. Beam and windage ask for good line handling; bow and stern thrusters cut the workload for a couple.
Range → Loop Legs
200400600 nmapprox. 396 nm at 8.2 kt before reserve — derived from official 2.2 NM/G performance table × 180 gal fuel builder-statedlong fuel-scarce stretches
The arc clears the long fuel-scarce stretches that shape Loop planning, with margin for sitting out weather rather than chasing fuel.
Great Loop Fit

The R-31 has a strong Great Loop argument because it combines shallow draft, low-to-moderate bridge clearance, diesel range, compact length, and enough accommodation for a cruising couple. At 30 inches of draft, it removes much of the shallow-water pressure that shapes the ICW, Okeechobee decision-making, canal edges, side trips, and marina approaches.

Bridge clearance depends on the variant. The R-31 S is straightforward: Ranger publishes 13'10" mast-up and 10' mast-down, both well below the 19'6" unavoidable fixed-bridge constraint commonly cited for the Loop. The R-31 CB is still workable on paper but more route-aware: 18'2" bridge and mast up, versus the 19'6" governing limit. That leaves about 16 inches before accounting for load, gear, antennas, measurement assumptions, water levels, and actual installed equipment.

Fuel and speed give the R-31 two operating personalities. Ranger states a 16-knot cruise speed, while the official Volvo/Ranger performance bulletin shows 15.5 knots at 3000 rpm and 8.2 knots at 3.7 gph / 2.2 nautical miles per gallon. The boat can run efficiently at displacement-minded speeds on rivers, then use speed when weather windows, daylight, or open water make that useful.

Where It Asks For Compromise

The first compromise is trailerability. Ranger calls the R-31 trailerable, but 10 feet of beam is not the same story as an 8'6" boat. Owners should think in terms of permits, route planning, tow vehicle, storage logistics, and occasional repositioning rather than casual weekend towing.

The second compromise is variant-specific. The R-31 S is the cleaner bridge-clearance boat. The R-31 CB is the more social and scenic boat, but its 18'2" published height deserves respect. A captain choosing the CB for the Loop should confirm actual height with mast, radar, antennas, canvas, gear, and normal load.

The third compromise is domestic scale. Two staterooms are a major advantage in a 31-class tug, but the boat remains compact. Storage, privacy, tankage, and quiet time are all finite. It can cruise a couple seriously, but it is not a broad liveaboard trawler.

Harbormaster's View

The Ranger Tug R-31 is a useful reminder that 'trailerable trawler' is not one idea. It is a spectrum. The R-31 still belongs to Ranger's road-mobile imagination, but it has crossed into a larger, more deliberate kind of mobility.

That middle position is what makes it interesting for the Great Loop. The R-31 gives a couple more of the things that make long cruising livable: a proper diesel, two sleeping cabins, a bigger cockpit, more seating, a protected helm, thrusters, diesel heat and air conditioning, and enough speed to change the shape of a travel day.

The choice between Sedan and Command Bridge is not cosmetic. The Sedan is the cleaner Loop profile: lower, simpler, less exposed, and easier to explain under bridges. The Command Bridge gives the boat a different pleasure: outdoor visibility, social seating, upper-helm perspective. It also asks the captain to care about inches. At 18'2" published height, it remains under the usual governing bridge number, but not by the casual margin of the Sedan.

Where Pricing Sits
Builder-published ready-to-cruise prices
R-31 S: $449,937 / R-31 CB: $484,937
VERIFY
Ranger publishes ready-to-cruise prices for both variants. Taxes not included; dealer prep and freight may apply. Options, equipment, specifications, and prices may change without notice.
Who It's For

Put it on the shortlist if

A couple or small family who wants a compact diesel Ranger with more accommodation than the smaller outboard models, shallow draft, a real cruising cockpit, two sleeping cabins, and the option of Command Bridge life without moving into a full-size trawler.

Look elsewhere if

Buyers who want legal-width trailering, maximum simplicity, large liveaboard storage, a low-cost new boat, or the bridge-clearance margin of the smaller Rangers. Also look elsewhere if a true displacement cruising rhythm matters more than Ranger's faster, feature-rich, semi-displacement personality.

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