The evolution of the SpaceX Merlin-1 engine
(and parameter)
 

 

 
Engine

Merlin-1A

Merlin-1Ci

Merlin-1C

Merlin-1CV

Merlin-1C+

Merlin-1D

Merlin-1DV

Merlin-1D+ Merlin-1DV+
Use Falcon-1
(Demo)
Falcon-1
(interim upgrade)
Falcon-1e
Falcon-9 (B1)
Falcon-9 (B1) Falcon-9 (B2)
(not realized)
Falcon-9 (v1.1) Falcon-9 (v1.1) Falcon-9 (v1.2) Falcon-9 (1.2)
 

 


 


 



 without nozzle extension



 


 


 



 



 
Propellant mix 2.17 2.17 2.17 2.17 2.17 2.34 2.36 2.36 2.38
Net flow rate (kg) 130.50 133.16 161.39 157.95 202.44 236.63 236.56 298.70 273.70
Thrust sea level

73,000 lbf

78,400 lbf 95,000 lbf - 122,700 lbf 147,100 lbf - 190,000 lbf -
Thrust vacuum

83,000 lbf

88,700 lbf 108,500 lbf 117,000 lbf (?) 138,800 lbf 166,900 lbf 181,000 lbf 205,500 lbf 210.00 lbf
Isp s.l. (sec) 253.7 264.5 267  - 275 282 - 288.5 -
Isp vac (sec) 288.5 302.5 304.8 336 311 320 347 312 348
Chamber pressure

5.39 MPa

6.08 MPa 6.14 MPa 6.14 MPa 6.77 MPa 9.72 MPa 9.72 MPa 10.8 MPa 10.8 MPa
Pressure exp. rate

 ?

 ?

?  ? ? 226 3240 227 3170
Throat area (m2) ? ? ? 0.042 ? 0.042 0.042 0.042 0.042
Nozzle area (m2) ? ? ? 4.90 ? 0.90 4.90 >0.90 >4.90
= Area exp. ratio 14.5 16 16 117 ? 21.4 117 >21.4 >117
Nozzle L/D (m) - - - 2.70 x 2.50 - - 2.70 x 2.50 - >2.70 x 2.50