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The Pro Boat Blackjack 42 8S catamaran review question isn't really whether it can hit 55+ MPH — it's how usable that speed is on real water. The catamaran vs deep-V vs mono hull guide explains the aerodynamic lift that makes this twin-sponson platform so quick yet so sensitive to setup, and that sensitivity shapes every part of Blackjack 42 ownership.
Horizon Hobby introduced the Blackjack 42 in 2021 as a large-scale brushless catamaran, and the same PRB08043 platform remains current in two cosmetic variants — Black/Orange and White/Red. There is no separate V2 or 42-inch 6S model. The same hull accepts 3S or 4S battery pairs, so a 6S setup is simply a lower-voltage configuration of the 8S boat.
This review goes beyond the manufacturer sheet. It looks at how the boat behaves at speed, why blowovers dominate owner discussions, what the 5–7 minute runtime really means, and which upgrades actually help rather than just adding heat or cost.
It's aimed at experienced RC boaters who have open water for a 42-inch catamaran, are comfortable tuning strut angle and battery position, and understand that a boat this fast demands a retrieval plan.
| Specification | Detail |
|---|---|
| Platform | PRB08043 — two colorways |
| Hull type | Catamaran |
| Hull material | 2.5 mm impact-resistant polycarbonate with molded internal structure |
| Length | 42.75 in / 1086 mm |
| Beam | 15.25 in / 387 mm |
| Height | 7.25 in / 184.15 mm |
| Weight | approx 8.95 lb / 4.1 kg |
| Motor | Spektrum Marine 4685, four-pole, 1350Kv, water-cooled |
| Motor specs | 2S–8S input, 4000W at 8S, 70A continuous, 46 mm × 85 mm, 5 mm shaft |
| ESC | Spektrum Smart 160A High Voltage water-cooled marine ESC |
| Servo | Spektrum S904 1/6-scale waterproof digital steering servo |
| Radio | Spektrum DX3 transmitter + SR6110AT six-channel telemetry receiver |
| Drive | Flex shaft, adjustable aluminum strut, single aluminum rudder |
| Propeller | approx 1.7 × 1.6 in, two-blade, on 5 mm shaft |
| Batteries required | Two 3S–4S 5000mAh 50C+ LiPos with EC5/IC5 connectors; two 4S packs for full 8S |
| Charger | Not included |
| Runtime | approx 5–7 min continuous full throttle |
| Manufacturer speed claim | 55+ MPH |
| Manufacturer power claim | up to approx 5.3 hp |
| Included | RTR electronics, DX3 transmitter, boat stand; no batteries or charger |
Quick verdict: The Blackjack 42 is a genuinely large, fast 8S catamaran with strong straight-line presence, but it is not a self-righting basher. Budget for two 4S LiPos, a compatible charger, and a recovery method, and expect to tune battery position and possibly fit trim tabs before exploring full speed. If you want a self-righting boat, look elsewhere; if you want a 42-inch twin-hull speed machine with real tuning depth, the Blackjack 42 is a strong premium pick.
Pro Boat Blackjack 42 — Overview & First Impressions
At 42.75 inches long and 15.25 inches wide, the Blackjack 42 is one of the largest ready-to-run electric catamarans in Pro Boat's lineup. The boat weighs about 8.95 pounds ready to run without batteries, and the 2.5 mm polycarbonate hull keeps that number lower than a fiberglass hull of similar size would be.
The first impression is scale. The twin-sponson layout decouples straight-line stability from hull weight, and the hull reads as fast even on the stand. Two color schemes — Black/Orange and White/Red — cover the same hardware, with no documented performance difference between the two.
Around the hull, the boat uses an adjustable aluminum propeller strut, a single aluminum rudder, and a polycarbonate canopy secured with aluminum thumb screws instead of a conventional taped hatch. The included DX3 transmitter and SR6110AT telemetry receiver provide Smart battery and ESC data when paired with compatible Spektrum equipment.
For context on how this hull type compares to deep-V and mono setups, see the RC boat buyer's guide and the catamaran vs deep-V vs mono hull guide.
Specs & What's in the Box
The table above covers the key measurements. What matters in practice is what RTR does and doesn't include.
Included in the box:
- Spektrum Marine 4685 1350Kv water-cooled brushless motor
- Spektrum Smart 160A High Voltage water-cooled marine ESC
- Spektrum S904 waterproof digital steering servo
- Spektrum SR6110AT six-channel telemetry receiver
- Spektrum DX3 transmitter
- Adjustable aluminum propeller strut and single aluminum rudder
- Boat stand
Not included:
- LiPo batteries
- LiPo charger
- Any additional recovery equipment
Full 8S operation requires two 4S 5000mAh packs. A 6S setup uses two 3S packs on the same boat. 50C or higher discharge is commonly listed, and some full-power setups use higher-discharge packs. The official full-throttle runtime estimate is roughly 5–7 minutes, so carrying multiple battery sets is realistic for a full session. For C-rating and connector guidance, see the RC boat battery guide.
The Black/Orange model is available here: Check Price on Amazon. The White/Red model is available here: Check Price on Amazon.
Build Quality & Durability
Polycarbonate has real benefits on a boat this size. It is lighter than gel-coated fiberglass and less prone to cosmetic chips during transport. RC Car Action's hands-on review noted the material as convenient and impact-resistant in normal handling.
That does not make it crash-proof. A 2026 owner report documented a severe rear-hull tear after a high-speed flip. That is a real incident, not evidence that every Blackjack 42 hull is defective — crashes at 55+ MPH can damage almost any RC hull. But the incident highlights why recovery planning matters so much with this boat.
Some water ingress is normal even with the polycarbonate canopy. RC Car Action found a small amount of water in the hull after running. The aluminum thumb screws make hatch access easier than tape, but hatch seals still deserve routine checks before high-power passes. If water entry becomes persistent, follow the RC boat waterproofing guide.
The flex shaft needs attention after use. The manual calls for removing, cleaning, and lubricating the shaft after running, and for keeping 1–2 mm of driveline clearance between the drive dog and strut because the flex shaft shortens under load. See the flex shaft and drive shaft guide for maintenance details.
Performance — Spektrum 8S Power, Handling & Top Speed
The powertrain is the headline. The Spektrum Marine 4685 motor is rated for 2S–8S operation, 4000W at 8S, and 70A continuous. The 160A High Voltage Smart ESC supports the full 8S range. Pro Boat's power claim is up to approximately 5.3 hp, and the result is aggressive acceleration.
The official 55+ MPH claim should be treated as condition-dependent, not a guaranteed GPS number. RC Car Action's testers did not pursue a top-speed run on their crowded, windy lake because the bow became noticeably light under hard throttle. Owners report porpoising and blowovers when the boat is trimmed aggressively or run in wind and chop.
Battery position is a tuning variable, not a fixed setting. Moving packs forward increases stability in wind or chop; moving them rearward lets the bow rise and can add speed in calm water, but also makes the boat less stable. Strut angle follows the same trade-off: raising it can add top speed but reduce steering authority and increase cavitation, while lowering it improves steering at the cost of maximum speed.
Runtime is short by design. Continuous full-throttle running lasts roughly 5–7 minutes on the recommended packs. There is no separate 6S model — running two 3S packs is simply a lower-voltage configuration of the same platform. For a deeper look at strut angle and trim setup, see the RC boat tuning guide.
Pro Boat Blackjack 42 vs Blackjack 24 — Head-to-Head
If the Blackjack 42 is more boat than a given pond can handle, Pro Boat's own Blackjack 24 is the natural step down. The two share the catamaran layout but differ sharply in scale and power.
| Category | Blackjack 42 | Blackjack 24 V2 |
|---|---|---|
| Length | 42.75 in | 24 in |
| Motor | Spektrum Marine 4685 1350Kv | Spektrum Firma 3660 2200Kv |
| ESC | Spektrum Smart 160A High Voltage | Spektrum Smart 90A |
| Battery configuration | Two 3S–4S packs, up to 8S | 4S |
| Notable running hardware | Adjustable aluminum strut | SSL battery tray, breakaway rudder |
The Blackjack 42 is the premium, open-water flagship; the Blackjack 24 is a more compact 4S catamaran intended for smaller running areas. Neither replaces the other — the 42 is about large-scale presence and 8S acceleration, while the 24 is easier to manage on a smaller lake or pond.
For a broader look at fast electric hulls, see the best RC speed boats rankings.
Recommended Upgrades / Best Accessories
- Setup before parts. Battery position and prop-strut angle are the highest-priority tuning changes because both are explicitly documented in the Pro Boat manual. No purchase required.
- Trim tabs. A commonly recommended handling upgrade among owners. They reduce porpoising and help keep the bow planted in less-than-perfect water. See the tuning guide for setup details.
- Cooling-system security. Inspect tubing and fittings before hard running. Small hose clamps or retainers are inexpensive insurance against a cooling line being forced off under high-speed water pressure. See the motor and ESC cooling guide.
- Higher-flow dual cooling circuit. Useful primarily for modified or harder-run setups, not a requirement for a stock boat.
- Flex-shaft maintenance supplies. Grease and cleaning tools are reliability upgrades, not speed upgrades. See the flex shaft guide.
- Aftermarket propeller. Only after establishing baseline temperatures and cooling flow. Any prop change should include incremental testing and temperature checks. See the propeller guide.
- Recovery boat or kayak. Practically essential because the Blackjack 42 has no self-righting. A capsize far offshore turns a fast outing into a retrieval problem.
- Avoid 12S as a normal upgrade path. 12S conversions exist in the enthusiast community, but they require substantial electronics and cooling changes and materially increase thermal and mechanical stress.
Who Should Buy the Pro Boat Blackjack 42?
Buy the Blackjack 42 if you want a large, genuinely fast electric catamaran with 8S power and are prepared for the full cost of ownership: two 4S LiPos, a compatible charger, flex-shaft maintenance, and a recovery method.
Skip it if you want a self-righting boat, a small pond basher, or a beginner-friendly first RC boat. This is a boat that rewards experienced throttle control and setup discipline. For models that flip back over automatically, see the RC boat self-righting guide.
Frequently Asked Questions
Q: Is the Pro Boat Blackjack 42 self-righting?
No. The catamaran hull floats inverted if it capsizes, and there is no flood chamber or self-righting system. A recovery boat, kayak, or keeping the boat within retrieval range is practically mandatory when running at speed.
Q: What batteries does the Blackjack 42 need?
Full 8S operation uses two 4S 5000mAh LiPo packs with EC5 or IC5 connectors. The same boat can run on 6S with two 3S packs. 50C or higher discharge is commonly listed, and some full-power setups use higher-discharge packs. A compatible LiPo charger is sold separately.
Q: How fast is the Blackjack 42?
Pro Boat rates it for 55+ MPH. Independent GPS verification varies, and maximum speed depends on wind, water conditions, battery placement, and strut angle. Treat 55+ as a manufacturer rating rather than a guaranteed number on every run.
Q: Does the Blackjack 42 include batteries and charger?
No. The boat ships ready-to-run with motor, ESC, servo, receiver, and transmitter installed, plus a boat stand. Batteries and a compatible charger are not included, and they add materially to the total cost.
Q: Are trim tabs necessary on the Blackjack 42?
Not mandatory, but they are a commonly recommended handling upgrade among owners. They help control porpoising and keep the bow planted in less-than-perfect water. A properly adjusted stock boat can still be enjoyable without them.
Q: Can the Blackjack 42 run on 12S?
Some owners have built 12S conversions, but that requires substantial electronics and cooling changes and greatly increases thermal and mechanical stress. It is modification territory, not a normal next step for most buyers.
Conclusion & Final Verdict
The Pro Boat Blackjack 42 earns its place as a premium large-scale catamaran when judged on scale, acceleration, and tuning depth — not on an isolated GPS number. The 55+ MPH claim is credible as a manufacturer rating, but usable speed matters more. This boat is already extremely fast at 45–55 MPH, and most owners get more value from stable handling than from chasing the last few miles per hour.
Recurring themes from owner experience are blowover risk, no self-righting, short runtime, and maintenance. Plan for two battery sets, a cooling check before each session, flex-shaft lubrication after use, and a recovery method. These are the real ownership costs, more than the boat itself.
For further reading, see the catamaran vs deep-V vs mono hull guide, the best RC speed boats rankings, the Pro Boat brand guide, and the RC boat tuning guide. If the Blackjack 42 fits your water and your budget for the extras, check current availability: Check price on Amazon.
