Editing Apollo 10 (section)

====Lunar landing capability====
{| class="wikitable plainrowheaders floatright"
|+ Comparison of LM weights
|-
! scope="col" rowspan=2 | Component
! scope="col" colspan=2 | Apollo 10 LM-4
! scope="col" colspan=2 | Apollo 11 LM-5
|-
! scope="col" | {{abbr|lb|pound (mass)}}
! scope="col" | {{abbr|kg|kilogram}}
! scope="col" | lb
! scope="col" | kg
|-
! scope="row" | Descent stage dry{{sfn|Orloff|2004|pp=276–277}}
| {{cvt|4,703|lb|kg|disp=table}} || {{cvt|4,483|lb|kg|disp=table}}
|-
! scope="row" | Descent stage propellant{{sfn|Orloff|2004|p=295}}
| {{cvt|18,219|lb|kg|disp=table}} || {{cvt|18,184|lb|kg|disp=table}}
|- style="font-weight: bold; background-color: #EAECF0;"
! scope="row" style="font-weight: bold;" | Descent stage subtotal
| {{cvt|22,922|lb|kg|disp=table}} || {{cvt|22,667|lb|kg|disp=table}}
|-
! scope="row" | Ascent stage dry{{sfn|Orloff|2004|pp=276–277}}
| style="background-color: #9f9" {{cvt|4,781|lb|kg|disp=table}} || {{cvt|4,804|lb|kg|disp=table}}
|-
! scope="row" | Ascent stage propellant{{sfn|Orloff|2004|p=296}}
| style="background-color: #f99;" {{cvt|2,631|lb|kg|disp=table}} || {{cvt|5,238|lb|kg|disp=table}}
|- style="font-weight: bold; background-color:#EAECF0;"
! scope="row" style="font-weight: bold;" | Ascent stage subtotal
| {{cvt|7,412|lb|kg|disp=table}} || {{cvt|10,042|lb|kg|disp=table}}
|-
! scope="row" | Equipment
| {{cvt|401|lb|kg|disp=table}} || {{cvt|569|lb|kg|disp=table}}
|- style="font-weight: bold; background-color:#EAECF0;"
! scope="row" style="font-weight: bold;" | Total{{sfn|Orloff|2004|pp=276–277}}
| {{cvt|30,735|lb|kg|disp=table}} || {{cvt|33,278|lb|kg|disp=table}}
|}

While Apollo 10 was meant to follow the procedures of a lunar landing mission to the point of powered descent, Apollo 10's LM was not capable of landing and returning to lunar orbit. The ascent stage was loaded with the amount of [[aerozine 50|fuel]] and [[nitrogen tetroxide|oxidizer]] it would have had remaining if it had lifted off from the surface and reached the altitude at which the Apollo 10 ascent stage fired; this was only about half the total amount required for lift off and rendezvous with the CSM. The mission-loaded LM weighed {{convert|30735|lb|kg|order=flip}}, compared to {{convert|33278|lb|kg|order=flip}} for the Apollo 11 LM, which made the first landing.{{sfn|Orloff|2004|pp=276–277}} Additionally, the software necessary to guide the LM to a landing was not available at the time of Apollo 10.<ref name="Hamish" />

Craig Nelson wrote in his book ''Rocket Men'' that NASA took special precautions to ensure Stafford and Cernan would not attempt to make the first landing. Nelson quoted Cernan as saying "A lot of people thought about the kind of people we were: 'Don't give those guys an opportunity to land, 'cause they might!' So the ascent module, the part we lifted off the lunar surface with, was short-fueled. The fuel tanks weren't full. So had we literally tried to land on the Moon, we couldn't have gotten off."<ref>[[#Nelson|Nelson 2009]], p. 14</ref> Mueller, NASA's Associate Administrator for Manned Space Flight, stated, <blockquote>There had been some speculation about whether or not the crew might have landed, having gotten so close. They might have wanted to, but it was impossible for that lunar module to land. It was an early design that was too heavy for a lunar landing, or, to be more precise, too heavy to be able to complete the ascent back to the command module. It was a test module, for the dress rehearsal only, and that was the way it was used.<ref>{{Cite web |date=April 9, 2019 |title=Apollo 10 |url=https://solarsystem.nasa.gov/missions/apollo-10/in-depth/ |url-status=dead |archive-url=https://web.archive.org/web/20220804181858/https://solarsystem.nasa.gov/missions/apollo-10/in-depth/ |archive-date=August 4, 2022 |access-date=June 19, 2022 |publisher=NASA Science}}</ref></blockquote>