Question: What engine type is used in a Space shuttle vacuum scenario?
SQL: SELECT "Engine type" FROM "1-15944-5" WHERE "Scenario" = 'Space shuttle vacuum';

Question: What is the effective exhaust velocity in a Space shuttle vacuum?
SQL: SELECT COUNT("Effective exhaust velocity (m/s)") FROM "1-15944-5" WHERE "Scenario" = 'Space shuttle vacuum';

Question: What is the maximum specific impulse with a 4423 m/s effective exhaust velocity?
SQL: SELECT MAX("Specific impulse (s)") FROM "1-15944-5" WHERE "Effective exhaust velocity (m/s)" = 4423.0;

Question: What is the SFC when the specific impulse is 453?
SQL: SELECT "SFC in g/(kN·s)" FROM "1-15944-5" WHERE "Specific impulse (s)" = 453.0;