Pearson 10M Info

Specs and Info

Pearson 10M Information   Hull # 212 	1978       DHP  6/15/2001, 8/28/03
Sail Number 212

PEARSON 10M DIMENSIONS        Notes:
LOA = 33.05                   length overall (on deck)          
Beam = 11.0                   beam overall
Draft = 5.93                  draft
LWL = 28.33 [1]               length waterline
Sail Area = 524 SF            sail area (100% foretriangle)
Displacement = 12,441 lbs [2]
Ballast = 5,445 lbs 
Mast Height Above LWL = 48        
BWL = 9.25  [3]               beam waterline
DISP CUFT = 181.53  [3]       displacement in cubic feet
DISP LBS S.W. = 11618  [3]    displacement in lbs of salt water
WA = 200.6 SQFT  [3][4]       wetted area of hull


DESIGN RATIOS                 Notes:
L/B = 3.0                     length to beam ratio
BR = 44                       ballast ratio
LWL/B = 2.57                  waterline length to beam ratio
LWL/BWL = 3.11                waterline length to waterline beam ratio
OR = 14%                      overhang ratio (LOA-LWL)/LWL
WPA = 170.4  [5]              Waterplane Area
WPL = 73.9 lbs/sf  [5]        Waterplane Loading (DISP/WPA)
CWP = .65                     Coefficient of the Waterline Plane
itWP = 810 feet⁴              Moment of intertia of the Waterline Plane
LBS/IN = 909  [3]             weight to imerse hull 1" below DWL
MT1 = 1096 FT LBS  [3]        Trimming Moment = moment to change trim by 1"
LPS = 123 deg  [6]            Limit of Positive Stability
Cp = 0.543  [3]               prismatic coefficient
LCB = 0.534  [3]              longitudinal center of buoyancy
VCB = -.81  [6]               vertical center of buoyancy above LWL
VCG = -.29  [6]               vertical center of gravity above LWL
SA/D = 15.6                   sail area displacement ratio
D/L = 245                     displacement length ratio
CSF = 1.9                     capsize screening formula
MCR = 26.3                    motion comfort ratio



More info on ratios
Polar Diagrams and Stability Curve
Calculation of Angle of Vanishing Stability

N O T E S
[1] The LWL of the 10M is listed in different Pearson literature as 28'4" and 29'2". The line drawing (Pearson drawing #1953) says 28'4" and the LWL does measure 28'4" on the drawing. 28'4" is the dimension used here for all calculations that involve LWL. For an LWL of 29'2" the following design ratios would be different:
D/L = 224, LWL/B = 2.65, LWL/BWL = 3.21, OR = 12%, MCR = 25.8

[2] This displacement figure (12,441 lbs) is the published number in Pearson literature. If this is the displacement for boats equipped with the A4 engine Volvo diesel boats can be assumed to be roughly 200 lbs heavier. USYRA measurment data for five 10M's weighed for IMS gives weights ranging from 12,048 to 13,143. These boats would have D/L ratios ranging from 237 to 258.

[3] These figures are taken from Pearson drawing #1953. If you know what some of these abreiviations mean email me.

[4] I think the wetted area of the hull does not include the keel and rudder area. They would add about 66 sqft to make the total wetted surface about 266 sf. That would be the figure needed for bottom paint calculations.

[5] Waterplane loading is a good indicator of comfort in a seaway (See "The Nature of Boats" by David Gerr, Ch 14). The lower the waterplane loading the faster the heave acceleration. That means the boat will bob up and down faster and be more uncomfortable. The 10M is well into Gerr's comfortable range.

[6] These figures are from a USYRA stability report for a particular 10M measured for MHS (early IMS). Also see the page on Angle of Vanishing Stability (AVS).

10M PHRF Ratings
Ratings vary between regions based on prevailing conditions and within regions based on boat equipment.

Boat

Average

Schell
Regression
Formula

spin

jam

146.3

168.3

143.3

Average rating does not include Schell regression formula rating.
Ratings for all Pearsons

MAST

  Mast height from water = 48' (TM 50')
  Top of antena from water = 52'
    Extrusion Specs
      Extrusion - Sound Spars 8755 tapered (8755T?)
      Dimensions (extrusion only)
        length              49.6' (TM 51.5')
        overall size        8.75" x 5.5"
        sail track          5/8"
        wall thickness      0.16"
        weight              4.8 lb/ft = 238 lbs
        moments of inertia  16, 33 in^4

Mast boot SS-8755MB (info from rigrite.com)
Mast Boot to fit Sound Spar 8755 and 8755T Oval Mast Sections (8.75" x 
5.5") and special Pearson Cast Deck Collar. Hard molded white PVC Mast 
Boot is 2 3/4" high x 10 3/4" long x 8" wide. As used on Pearson 36, 419, 
424 and 10M.



  Spreaders - aluminum airfoil sections
    length =  38-1/2" (-1/2 to wire center)
    width = 4-1/2" tapers to 2-1/4" stating 14" from base
    thickness = 1-1/2" tapers to 1/2" stating 14" from base
  The spreaders may be RigRite SP450.

  sheaves - aluminum with bronze bushings
    overall diameter      3.75"
    diameter at groove    3.25"
    thickness             0.625"
    bushing OD (apr)      0.65"
    bushing ID            0.518" [7]
    shaft diameter        0.500"

[7]Measurement after 24 years of service

BOOM

 actual measured dimensions (extrusion only)
  Wall thickness  
	   Overall	Inside
  length    11'4"
  height     6"
  width	     4"

  length to forward edge of stripe 
  sail track  slot width

WINCHES (OEM)

  2 Lewmar #8 halyard
  2 Lewmar #43 2 speed sheet
 (2 Lewmar #30 2 speed spinnaker sheet)

RIGGING (as specefied in the 1977 parts catalog)

  Wire           Type  Diam  Length [8]  pin-to-pin [9]
  Headstay       1x19   3/8   43.438       45.17
  Backstay       1x19   3/8   44.813       46.36
  Upper Shrouds  1x19  5/16   40.771       41.96 
  Lowers         1x19  9/32   21.666       22.88
  Fwd Lowers     1x19  9/32   21.708       22.95
  Topping Lift   7x19

[8] length of wire only, no turnbuckles or toggles (from Pearson parts catalog) - This will be correct only for the OEM Navtec turnbuckles
[9] As measured on hull #212 after careful rig tuning (fall 2001), pin-to-pin is chainplate to mast fitting including toggles and at pin centers.

 TURNBUCLES		  Size
  Headstay  		 
  Backstay (base) 	 
  Shrouds  	 	

10M #212 CLEVIS PIN SIZES
 CLEVIS PINS              Diameter    Length
  headstay                5/8"        1"
  backstay                5/8"        1"
  upper shrouds top       5/8"        1"
  upper shrouds bottom    5/8"        7/8"
  lower shrouds top       1/2"        3/4"
  lower shrouds bottom    1/2"        7/8"


 RUNNING
  Line          Size    Length
  main H         3/8     83'
  jib H          3/8     90'
  spin H         3/8     90'
  outhaul       
  traveler      
  topping L     
  pole lift     
  pole DH       
  mainsheet      1/2     82'
  jib sheet      7/16    40'
  genoa sheet    7/16    48'
  spin sheet             66'
  asym sheets            75'

  Note: Halyard lengths are at the mast.  Add about 14' to run back to cockpit.
 
KEEL
 Lead
 Weight 5445 lbs
 5/8" Bolts 
 Torque 70 lb-ft [10]

[10] Source: Bill Shaw in Pearson Current news letter Vol. 4 #3, 1998.



RUDDER
 Construction

 Actual measured dimensions
  Shaft OD = 1.5"

Sail Dimension Information

All dimensions in feet.

Mast height from water = 48' (50' TM)
Standard       #212       Tall Mast    Tall Mast/Sprit [11] 
I = 44.0'    I = 44.5'    I = 46.0'    I = 46.0'      
J = 14.2'    J = 14.2'    J = 14.2'    J = 15.5'
P = 38.5'    P = 38.5'    P = 40.5'    P = 40.5'
E = 11.0'    E = 11.0'    E = 11.0'    E = 11.0'
SA= 524sf    SA= 528sf    SA= 549sf    SA= 579sf   (sail area)
MA= 212sf    MA= 212sf    MA= 223sf    MA= 223sf   (main area)
FA= 312sf    FA= 316sf    FA= 327sf    FA= 357sf   (100% fore triangle area)

[11] Sprit was factory option.  It added about 15" to the J dimension.  Not sure about exact measurement. (photo)


SAIL    LUFF    LEECH    FOOT    LP     AREA    %J      Wt
Main    38.5             11.0            212    
#1      42.0     41.0    21.7   20.6     433   145
#2      41.2     35.4    20.6   17.8     370   125       
#3      40.7     34.0    16.3   13.4     272    94     7.5
WJib     
Drift   

Spin	

Spinnaker Dimensions by IOR formula:
Max Girth = 1.8 x J = 1.8 x 14.2' = 25.56'
Luff = .95 x (J^2 + I^2)^1/2 
     = .95 x (14.2^2 + 44.0^2)^1/2
     = 43.92'


S Y S T E M S

HEAD
Jabsco 29120-0000
Repair parts kit  #29045-0000?  
W&C (213)632-2600
Intake 3/4" ID hose to seacock under head sink

HOLDING TANK
12 gallons
Hose Fittings: ??
L=24" W=13.9" H=9.75"

WATER TANKS
Forward
  Rectangular
  23.5 gallons (apr)
  1-1/4" filler hose fitting
  5/8" drain and vent hose fittings
  L=36" W=17.25" H=9"
Port/Starboard
  The ends are triangular with a slightly convex side (on the hull), with two baffles inside.
  25 gallons each (apr calculated from dimensions)
  1-1/4 filler hose fitting?
  5/8" drain and vent hose fittings?
  L=49.5 W(fwd)=20 H(fwd)=10.5
         W(aft)=24 H(aft)=11
Total capacity
  23.5 + 25 + 25 + 6 (water heater) = 79 gallons (56 without fwd tank)

POWER
ELECTRICAL
BATTERIES
2 group 27 deep cycle
Astro Lite 27DCM COMBO
reserve capacity 165
cranking amps 750
march 2000 install date



Propeller Shaft
hull #212, Volvo MD11C with Walter V-Drive
diameter = 1-1/8"
material = Aquamet 19 stainless steel (oem was bronze)
lenght to small end of taper = 49-5/8"
thread length = 1-1/16" (to fit J-Prop feathering propeller)
thread = 3/4x10tpi
cutlass bearing = 1-1/8 ID, 1-1/2 OD, 4-1/2 long
 
Stuffing Box ( hull 212 with 1-1/8" diameter prop shaft)
packing size = 3/16"
Packing length = apr 4-3/8", 24" will make 5 pieces, 4 fit in gland
Stuffing Box Hose = 2-1/4" ID


E L E C T R I C   D R I V E   S Y S T E M   2 0 2 1
Electric Drive

Electric Motor
Motor: Motenergy ME1616 Liquid Cooled
Operating Voltage: 48 (as installed)
Max RPM @48V: 2400
Max continuous power with cooling/no cooling: 12kW / 6.7kW
Max Temp: 160C
Coolant Flow: 4 to 10 liters/min
Weight: 25.2 kg (56 lbs)

Traction Battery
LiFePo (16) Prismatic Cells
Thunderstruck BMS
Battery Voltage: 48
Battery Capacity: 13,400 Whr
Useable Capacity at 80% DoD: 10,720 Whr
Max Output: 13.4kW (1.0 C rating)
Assembled Weight: apr 200 lbs (w/case, bms, buss bars, etc)
Dimensions: 29.25x13x10.25 (LxWxH)

Charging
Charger: Thunderstruck EV TSM2500
Time to Fully Recharge: 7 hrs at 1500 watts


O E M   D R I V E   T R A I N   1 9 7 8
Engine
Volvo MD11C diesel
2 cylender
hp = 23 @ 2500 RPM
Oil Filter Fram PH3614
weight = 505 lbs

Transmission
Volvo Monoshift (no reduction, w/reverse gear)

V-Drive
Walter RV-10 SN 33097 (back-up SN 36615)
2:1 reduction gear
Flange Dimension 
Overall diameter =  2.875
Counter bore = 1.250 - female on coupling
bolt circle = 1.875 - 3 bolts
Spicer bearing kit
  Dana 5-170X
  G200208190126 - SLK
  UPC 7 25975 11520 6
Upper Seal 
  National Federal - Mogul Oil Seals 471765 1.187 x 2.000 x 0.250

Numbers from parts in v-drive SN 33097 
Upper shaft bearings 
  #14
  Timken 17244 outer race
  Timken 17118 inner race
  #14A
  race marked Timken 07204

Lower shaft bearings
  #15   
  NACHI 5304 (replacement sent by Walter)
  15A
  race marked Timken 07204

Output Shaft Seal #8
  WP 15104-LBS marked on seal

Hoses
intake to strainer 3/4"
strainer to v-drive 5/8"
v-drive to water pump 5/8"
water heater 5/8"
engine to exhaust riser 5/8"
exhaust elbow to muffler 1-5/8"
exhaust muffler to stern 1-1/2"

Stanchions
Angle of deck at stanchion positions as measured 10/2018
Stanchion position - deck angle
#1 - 6 degrees
#2 - 7 degrees
#3 - 9 degrees
#4 - 8 degrees
+/- 1/2 degree
Stanchion positions are moving aft


Angle of stanchion bases
Two with 3 degree angle
four with 6 degree angle
two with 9 degree angle


Galley Sliding Doors
Dimensions 14-1/8" x 25-3/8" x 1/8" to 3/16" thick