The citation for the wikipedia page (240s ISP) gives an exhaust velocity of 2,300m&#x2F;s :<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;SuperDraco#cite_note-DragonFlyEAI201403-4" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;SuperDraco#cite_note-DragonFly...</a> - page 12 of the PDF.<p>So taking a rough 2300&#x2F;9.8 gives about 235s