KW rocketry Vesta VR-1 versus Aerospike rocket

[gilflo]

Vesta VR-1: Thrust 120; Weight 0,6 ; ISP ground 350; ISP vacuum 410

Aerospike: Thrust 175; weight 1,5 ; ISP ground 388; ISP vacuum 390

If you fit any small or medium tank with an Aerospike and the same one with 2 Vesta VR-1, you realize that, except near the ground you won't get more DV with the Aerospike.

The advantage on the first 5000m is 10% more DV, which become a disadvantage when you climb, the Vesta VR-1 getting a better Isp, and 2 Vesta getting 30% more thrust which means a better TWR.

That's why I choose the VR-1 for my Eve lander.

Lander is lighter, TWR is better, total vacuum DV is much better and, if needed, you can arrange a decoupler on the Vesta, you cannot do it on aerospace.