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- Thread starter gary
- Start date Feb 9, 2006
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- Feb 9, 2006
I dont have any experience with the SR 21. Any thoughts or opinions? Look like good club racers?
- Thread starter
They go GREAT !!! Just about the perfect 21 foot keel boat. Too bad the keel lifting mechanism, or the lack thereof, never was too popular. The boat has wonderful lines, keel and rudder shape, as do all the Hendersons, and I would say fairly well made...untill C & C came into the picture. As far as speed goes....I've seen Mr. Glenn Henderson/Putz out sail and out run a number of serious sailboats that an SR MAX has no business being any where near...much less ahead of boat for boat. The more wind the better....
quitpinchin
Super anarchist.
Two words. Giant Killer.
Cement_Shoes
That chute looks like a kid dressed up as a ghost for halloween.
dolphinmaster
quitpinchin said: Two words. Giant Killer. Click to expand...
mustang__1 said: quitpinchin said: Two words. Giant Killer. Click to expand...
Giant Killer - really - not from my experience - maybe it was the crew!
Greig said: Giant Killer - really - not from my experience - maybe it was the crew! Click to expand...
- Feb 10, 2006
quitpinchin said: mustang__1 said: quitpinchin said: Two words. Giant Killer. Click to expand...
35degreesofheel
how do they compare to viper 640's? Holder 20s?
U20UFO said: Ah -- Holder 20? Not even in the same era.. Can't be comparedSR 21 is more in the family of the Rocket 22 - U20 - Viper 650 - T650 all very different boats but similar family. Click to expand...
So if it'll smoke an U20 or Viper 640, then why does a SR rate 170's, u20's rate 130's, Viper rates 110ish?
35degreesofheel said: So if it'll smoke an U20 or Viper 640, then why does a SR rate 170's, u20's rate 130's, Viper rates 110ish? Click to expand...
I think that the boat really needs the breeze to get fast.. The rating is all around. Unit- The pic came from Charlie's site...
islandplanet
35degreesofheel said: how do they compare to viper 640's? Holder 20s? Click to expand...
Price wise, isn't the U20 alot more than the SR21?
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- Sailboat Guide
SR 21 is a 21 ′ 1 ″ / 6.4 m monohull sailboat designed by Glenn Henderson and built by C&C Yachts starting in 1992.
Rig and Sails
Auxilary power, accomodations, calculations.
The theoretical maximum speed that a displacement hull can move efficiently through the water is determined by it's waterline length and displacement. It may be unable to reach this speed if the boat is underpowered or heavily loaded, though it may exceed this speed given enough power. Read more.
Classic hull speed formula:
Hull Speed = 1.34 x √LWL
Max Speed/Length ratio = 8.26 ÷ Displacement/Length ratio .311 Hull Speed = Max Speed/Length ratio x √LWL
Sail Area / Displacement Ratio
A measure of the power of the sails relative to the weight of the boat. The higher the number, the higher the performance, but the harder the boat will be to handle. This ratio is a "non-dimensional" value that facilitates comparisons between boats of different types and sizes. Read more.
SA/D = SA ÷ (D ÷ 64) 2/3
- SA : Sail area in square feet, derived by adding the mainsail area to 100% of the foretriangle area (the lateral area above the deck between the mast and the forestay).
- D : Displacement in pounds.
Ballast / Displacement Ratio
A measure of the stability of a boat's hull that suggests how well a monohull will stand up to its sails. The ballast displacement ratio indicates how much of the weight of a boat is placed for maximum stability against capsizing and is an indicator of stiffness and resistance to capsize.
Ballast / Displacement * 100
Displacement / Length Ratio
A measure of the weight of the boat relative to it's length at the waterline. The higher a boat’s D/L ratio, the more easily it will carry a load and the more comfortable its motion will be. The lower a boat's ratio is, the less power it takes to drive the boat to its nominal hull speed or beyond. Read more.
D/L = (D ÷ 2240) ÷ (0.01 x LWL)³
- D: Displacement of the boat in pounds.
- LWL: Waterline length in feet
Comfort Ratio
This ratio assess how quickly and abruptly a boat’s hull reacts to waves in a significant seaway, these being the elements of a boat’s motion most likely to cause seasickness. Read more.
Comfort ratio = D ÷ (.65 x (.7 LWL + .3 LOA) x Beam 1.33 )
- D: Displacement of the boat in pounds
- LOA: Length overall in feet
- Beam: Width of boat at the widest point in feet
Capsize Screening Formula
This formula attempts to indicate whether a given boat might be too wide and light to readily right itself after being overturned in extreme conditions. Read more.
CSV = Beam ÷ ³√(D / 64)
First introduced as SR MAX.
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- About Sailboat Guide
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The Sr 21 is a 21.08ft fractional sloop designed by Glenn Henderson and built in fiberglass by C&C Yachts since 1992.
The Sr 21 is a light sailboat which is a very high performer. It is stable / stiff and has a low righting capability if capsized. It is best suited as a day-boat.
See all sailboats built by C&C Yachts
See all sailboats designed by Glenn Henderson
Sr 21 for sale elsewhere on the web:
Main features
| Model | Sr 21 | ||
| Length | 21.08 ft | ||
| Beam | 8 ft | ||
| Draft | 0.92 ft | ||
| Country | United states (North America) | ||
| Estimated price | $ 0 | ?? |
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| Sail area / displ. | 26.39 | ||
| Ballast / displ. | 31.81 % | ||
| Displ. / length | 105.64 | ||
| Comfort ratio | 7.06 | ||
| Capsize | 2.88 |
| Hull type | Monohull lifting keel | ||
| Construction | Fiberglass | ||
| Waterline length | 18 ft | ||
| Maximum draft | 4.50 ft | ||
| Displacement | 1380 lbs | ||
| Ballast | 439 lbs | ||
| Hull speed | 5.69 knots |
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| Rigging | Fractional Sloop | ||
| Sail area (100%) | 204 sq.ft | ||
| Air draft | 0 ft | ?? | |
| Sail area fore | 80.15 sq.ft | ||
| Sail area main | 123.69 sq.ft | ||
| I | 22.11 ft | ||
| J | 7.25 ft | ||
| P | 25.53 ft | ||
| E | 9.69 ft |
| Nb engines | 1 | ||
| Total power | 0 HP | ||
| Fuel capacity | 0 gals |
Accommodations
| Water capacity | 0 gals | ||
| Headroom | 0 ft | ||
| Nb of cabins | 0 | ||
| Nb of berths | 0 | ||
| Nb heads | 0 |
Builder data
| Builder | C&C Yachts | ||
| Designer | Glenn Henderson | ||
| First built | 1992 | ||
| Last built | 0 | ?? | |
| Number built | 0 | ?? |
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Review of SR 21
Basic specs..
The hull is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season. And outside the sailing season, just bottom cleaning and perhaps anti-fouling painting once a year - a few hours of work, that's all.
DaggerBoard aka Sword
The SR 21 is built with a daggerboard keel. A daggerboard is a lifting keel that can be lowered and raised, allowing the boat to enter shallow waters as well.
The boat can sail close to the beach as the draft is just 0.28 - 0.38 meter (0.92 - 1.22 ft) dependent of the load. See immersion rate below.
Sailing characteristics
This section covers widely used rules of thumb to describe the sailing characteristics. Please note that even though the calculations are correct, the interpretation of the results might not be valid for extreme boats.
What is Theoretical Maximum Hull Speed?
The theoretical maximal speed of a displacement boat of this length is 5.7 knots. The term "Theoretical Maximum Hull Speed" is widely used even though a boat can sail faster. The term shall be interpreted as above the theoretical speed a great additional power is necessary for a small gain in speed.
The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for SR 21 is about 89 kg/cm, alternatively 502 lbs/inch. Meaning: if you load 89 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 502 lbs cargo on the boat it will sink 1 inch.
Sailing statistics
This section is statistical comparison with similar boats of the same category. The basis of the following statistical computations is our unique database with more than 26,000 different boat types and 350,000 data points.
What is L/B (Length Beam Ratio)?
Maintenance
When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 16m 2 (172 ft 2 ). Based on this, your favourite maritime shop can tell you the quantity you need.
Are your sails worn out? You might find your next sail here: Sails for Sale
If you need to renew parts of your running rig and is not quite sure of the dimensions, you may find the estimates computed below useful.
| Usage | Length | Diameter | ||
| Mainsail halyard | 20.7 m | (68.0 feet) | 8 mm | (5/16 inch) |
| Jib/genoa halyard | 20.7 m | (68.0 feet) | 8 mm | (5/16 inch) |
| Spinnaker halyard | 20.7 m | (68.0 feet) | 8 mm | (5/16 inch) |
| Jib sheet | 6.4 m | (21.0 feet) | 10 mm | (3/8 inch) |
| Genoa sheet | 6.4 m | (21.0 feet) | 10 mm | (3/8 inch) |
| Mainsheet | 16.0 m | (52.5 feet) | 10 mm | (3/8 inch) |
| Spinnaker sheet | 14.1 m | (46.2 feet) | 10 mm | (3/8 inch) |
| Cunningham | 2.9 m | (9.6 feet) | 8 mm | (5/16 inch) |
| Kickingstrap | 5.9 m | (19.2 feet) | 8 mm | (5/16 inch) |
| Clew-outhaul | 5.9 m | (19.2 feet) | 8 mm | (5/16 inch) |
This section is reserved boat owner's modifications, improvements, etc. Here you might find (or contribute with) inspiration for your boat.
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We are always looking for new photos. If you can contribute with photos for SR 21 it would be a great help.
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C&c yachts, c&c sr 21.
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C&c sr 21 manufacturer: c&c yachts designed by: glenn henderson.
| LOA | 21.08′ |
| LWL | 18′ |
| Beam | 8′ |
| Draft (Deep) | 4.5′ |
| Draft (Shoal) | .92′ |
| Displacement | 1,380 lbs. |
| Ballast | 439 lbs. |
| Sail Area | 203.84 sq. ft. |
| Rig: I | 22.11′ |
| Rig: J | 7.25′ |
| Rig: E | 9.69′ |
| Rig: P | 25.53′ |
| Sail Area (Main) | 123.69 sq. ft. |
| Sail Area (100% Jib) | 80.15 sq. ft. |
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COMMENTS
Designed to determine if a boat has blue water capability. The CSF compares beam with displacement since excess beam contributes to capsize and heavy displacement reduces capsize vulnerability. The boat is better suited for ocean passages (vs coastal cruising) if the result of the calculation is 2.0 or less.
The SR 21 is a racing keelboat, built predominantly of fibreglass. It has a fractional sloop rig, a raked stem , an open reverse transom , an internally-mounted spade-type rudder controlled by a tiller and a lifting fin keel .
Jul 28, 2012 · SR 21--heavier than the Viper...probably a bit better upwind in slop. Rating ought to make up the difference in speed. SR 21 is not as wet as the Viper & should be better in the light stuff---it is a Henderson design, afterall.
Oct 14, 2004 · I am looking for a quick and relatively stable sport boat. SR 21 caught my eye and am looking at feedback and boats for sale in the northeast. I am aware...
Just about the perfect 21 foot keel boat. Too bad the keel lifting mechanism, or the lack thereof, never was too popular. The boat has wonderful lines, keel and rudder shape, as do all the Hendersons, and I would say fairly well made...untill C & C came into the picture.
SR 21 is a 6.4 m monohull sailboat designed by Glenn Henderson and built by C&C Yachts starting in 1992. The theoretical maximum speed that a displacement hull can move efficiently through the water is determined by it's waterline length and displacement.
The Sr 21 is a 21.08ft fractional sloop designed by Glenn Henderson and built in fiberglass by C&C Yachts since 1992. The Sr 21 is a light sailboat which is a very high performer. It is stable / stiff and has a low righting capability if capsized. It is best suited as a day-boat.
The SR 21 is equipped with a daggerboard keel. A daggerboard is a lifting keel that can be lowered and raised, allowing the boat to enter shallow waters as well. The boat can sail close to the beach as the draft is just 0.28 - 0.38 meter (0.92 - 1.22 ft) dependent of the load.
Blue Water Surf Value Rank (BWSVR) 7771. Capsize Comfort Value Rank (CCVR)
C&C Yachts C&C SR 21 < Return to C&C Yachts C&C SR 21 Manufacturer: C&C Yachts Designed by: Glenn Henderson LOA 21.08' LWL 18' Beam 8' Draft (Deep) 4.5' Draft (Shoal) .92' Displacement