21. These advantages were expected to overcome the disadvantages of small specific impulse and payload fraction. 22. This would have created immense toxicity problems but increased the specific impulse of the engine by. 23. Jet engines use outside air, and therefore have a much higher specific impulse than rocket engines. 24. Nonetheless, the high specific impulse of electrical thrusters may significantly reduce the cost of the flight. 25. When calculating specific impulse , only propellant that is carried with the vehicle before use is counted. 26. LMP-103S has 6 % higher specific impulse and 30 % higher impulse density than hydrazine monopropellant. 27. With higher fusions gains comes higher exhaust velocity, higher specific impulse and lower electrical power requirements. 28. The specific impulse of AF-M315E is 257 s. 29. Thus, the greater the specific impulse , the greater the net thrust and performance of the engine. 30. The theoretical specific impulse ( " I " sp ) range from 1500 to 3000 seconds.
