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A fact from this article was featured on Misplaced Pages's Main Page in the On this day section on April 9, 2004, April 9, 2005, April 9, 2006, April 9, 2007, April 9, 2008, April 9, 2009, and April 9, 2010.

Capsule volume discrepancy

Check out the following differing figures from the article, given for the Mercury capsule's volume:

• Spacecraft section: Only 12.13 cubic meters of volume (...)
• Data table: Volume: 60 ft³  1.7 m³

I wonder if a typo mighirockt've crept into the Spacecraft sec's number. My guess so far is that the correct number should be, say, 1.213 m³, and that it represents the capsule's internal volume. Any comments? --Wernher 19:54, 12 Oct 2004 (UTC)

states that the habitable volume was 1.7m³. There is often a bit of descepancy between various sources on things like volumes, capacities etc. --enceladus 21:23, 12 Oct 2004 (UTC)

It's been 8 years since this discrepancy was pointed out and it's still live... the Mercury did NOT have an internal volume of 12 meters, can we please get it corrected to something CLOSER to reality... or at least smaller then the Apollo CSM's volume? 97.125.180.25 (talk) —Preceding undated comment added 03:22, 14 June 2012 (UTC)

What are you on about, then? The number has been corrected in the article (1.7 cubic meters), which is about as good as we're likely to get. JustinTime55 (talk) 21:34, 2 October 2012 (UTC)

Image on the Left

What is it? Why is it not labeled?

• It is the Mercury program monument at pad 14. The entry in the article to include the image was missing the word "thumb". I believe that I have fixed it. Vaoverland 12:37, 13 November 2006 (UTC)

g-Forces

During reentry, the astronaut would experience about 4 g-forces. The separate mission articles say otherwise: Mercury-Redstone 3: 11.6 g, Mercury-Redstone 4: 11.1 g, Mercury-Atlas 6: 7.7 g, Mercury-Atlas 7: 7.8 g, Mercury-Atlas 7: 8.1 g, Mercury-Atlas 9: 7.6 g. So this might need to be corrected. --Proofreader 18:16, 10 January 2007 (UTC)

Not necessarily; the booster numbers are obviously giving the launch accelleration. Re-entry g-force is completely different, caused by the friction of the air, and is totally unrelated to the acceleration at launch, and would mainly be driven by re-entry speed. I would expect the orbital flights (M-A) to be perhaps a bit different (bigger?) than the suborbitals (M-R). JustinTime55 (talk) 22:29, 26 February 2010 (UTC)

Opps--I mis-spoke. The articles explicitly quote re-entry g's and are fuzzy or silent about the launch g's, so Proofreader is correct. The sub-orbitals probably pulled much higher re-entry g's because of the steeper ballistic trajectory. JustinTime55 (talk) 22:47, 26 February 2010 (UTC)

Launch Escape System

The article says the LES generated 52,000 lbs of thrust. With a launch weight of 4265 lbs, that works out to a little over 11 Gs. Is that really possible? Can people survive 11 Gs? -- RoySmith (talk) 01:29, 5 May 2008 (UTC)

I don't have the reference in front of me, but if I recall correctly, the maximum G force experienced (and survived) was 20--in a centrifuge. MWShort (talk) 19:19, 9 May 2008 (UTC)

reading John Glenn's memoir just recently, 16 gs was the max survivable "upper limit" that they found they could subject astronauts to if they had to and still be ok (due to heart/lung issues). Yes the LES would have kicked it higher very briefly, I imagine if it had come down to that kind of emergency situation they figure better to have the astronanut alive if hurt then nothing at all. —Preceding unsigned comment added by 166.56.100.23 (talk) 19:23, 23 January 2009 (UTC)

space capsule

The space capsule stuff should be expanded, perhaps into a separate article Mercury space capsule 70.55.203.112 (talk) 08:15, 28 September 2008 (UTC)

skin

Why is the skin on mercury (and gemini) currogated rather than smooth? Strength? What about drag? Bachcell (talk) 00:53, 21 January 2009 (UTC)

From what i've seen looking @ a few references, each capsule was built with some minor differences as they went along. Mainly I've seen the corrugated parts on the upper as opposed to the lower part of the capsules. For exmaple "The Recovery Section had corrugated Rene 41 shingles rather than the flat plate-type beryllium shingles used on manned flights." also "MR-2 and MR-3 were also unique in having a different main hatch. These two missions had a thick hatch with a relatively smooth surface, not corrugated like the shingles covering the capsule." so not positive but I would guess for strength mainly, as the LES was conected to that part up top. —Preceding unsigned comment added by 166.56.100.23 (talk) 19:31, 23 January 2009 (UTC)

Actually, those corrugations you see on the Mercury spacecraft are for keeping it cool rather than for strength. What you're looking at are the outer "shingles" on the spacecraft. The spacecraft's structural skin, which provides the strength, lies underneath the shingles. The shingles are corrugated to increase their surface area. That would give the spacecraft more surface area from which to radiate heat away into space while absorbing the same amount of sunlight.

I think they might also provide more surface area for air to flow over during atmospheric reentry, which would help remove heat during that stage. That would explain why the shingle corrugations run across the direction of airflow, rather than parallel to it as you might expect. That does increase drag, but only by a very small amount compared to the blunt heatshield, and the relatively slow turbulent airflow over the corrugations would efficiently carry away the heat that was conducted from the heatshield to the rest of the spacecraft.

During launch, the corrugations wouldn't increase the drag that much. The sharp aerospike at the tip of the escape rocket did a lot to reduce drag during the supersonic portion of the launch, when drag was at its worst, because it caused the supersonic shock wave to build up ahead of the rocket's main body.

--Colin Douglas Howell (talk) 08:47, 17 May 2009 (UTC)

Last American to orbit the Earth solo

The article describes Gordon Cooper as the "Last American to orbit the Earth solo", but isn't that actually David Scott, the Command Module pilot of Apollo 9? He orbited the Earth solo while the Lunar Module was being test flown. 70.153.127.71 (talk) 03:09, 27 July 2009 (UTC)

Cooper was the last American to orbit the Earth solo. No one else was in orbit at the time. To be more definitive, though, he was unequivocally the last American to be launched into orbit alone. —Preceding unsigned comment added by SEWalk (talk • contribs) 02:58, 23 October 2009 (UTC)

Bruce McCandless could also be considered an astronaut flying in solo orbit. I have modified the table remark. ShelbyBell (talk) 23:30, 24 June 2012 (UTC)

Mercury 13 section

I think this section should be removed. NASA never considered using women. This was all the idea of Lovelace, who had tested the Mercury Seven. Bubba73 , 04:02, 4 July 2010 (UTC)

There have been no objections, so I removed that section. It is mentioned in the See also section. Bubba73 , 15:24, 15 July 2010 (UTC)

Merge

The removal of the lists of unmanned and manned Mercury launches diminishes the utility of this article, to no discernible purpose. Relevant information should be grouped together for easy reference and comparison; having to go to several different articles for the relevant information significantly impairs the encyclopedic usefulness of the article. RandomCritic (talk) 03:42, 28 October 2011 (UTC)

Since there was no objection, I completed the merge. RandomCritic (talk) 19:06, 15 November 2011 (UTC)

I agree with this merge.--Craigboy (talk) 00:31, 20 November 2011 (UTC)

Interior volume of spacecraft

I had changed cubic meters to decimeters/liters since cubic meters seemed like a large metric to describe the volume and used both cubic decimeters and liters because cubic decimeters are the recognized but uncommon SI unit. I also added cubic feet in parentheses for three reasons:

1. The spacecraft was built by McDonnel in the 1950s in the US, and most likely designed to specifications described in US customary units.

2. As a convenience and courtesy to the smaller yet significant portion of the English language[REDACTED] readers who lack an intuitive scope of area defined by SI units.

3. A secondary metric of 60 cubic feet is also helpful to those readers familiar with both SI and US customary units.

The change was reverted, and while I concede to the reversion of the SI volume back to "cubic meters" on the proposed basis that liters are not as intuitive as cubic meters when describing volume, I object to the removal of the secondary metric given in "cubic feet". I intend to edit the secondary metric using "cubic feet" following "cubic meters" into the article in parentheses following the primary description in cubic feet. If it is removed afterwards I will accept the change and refrain from editing this detail in the future.

173.67.242.156 (talk) 11:05, 30 March 2012 (UTC)Moi

After reading the cited link, I discovered that the original interior dimensions were incorrect in the first place. According to centennialofflight.gov a website designed to provide public information on the history powered human flight run by the US government who also commissioned, owned and operated every Mercury spacecraft that was produced:

"The spacecraft that was designed was cone-shaped with a cylinder on top. It was 6.8 feet (2 meters) long, 6.2 feet (2 meters) in diameter, and had a 19.2-foot, (5.8-meter) escape tower with a solid-rocket motor fastened to the cylinder. In a launch emergency, the rocket would fire and lift the capsule from an explosion and parachute it into the ocean. With a volume of only 428.5 cubic feet (12 cubic meters), there was barely enough room for its pilot, who sat in a custom-designed couch facing a panel with 120 controls, 55 electrical switches, 30 fuses, and 35 mechanical levers. The cabin's atmospheric pressure was one-third of that on Earth and contained pure oxygen."

So while I previously stated I would no longer edit this detail, I must revise that to I will not reinsert the non SI metric if it is reverted but will ensure the proper SI metric of "12 cubic meters" is maintained if reverted back to the incorrect "1.7 cubic meters" metric.

(and just to be clear, my use of the term "metric" in these comments is not a reference to the "Metric System" but as a term describing any generic measurement irregardless* of the scale used)

• just kidding, I know the word is "regardless" sorry for those it made cringe.

173.67.242.156 (talk) 11:32, 30 March 2012 (UTC)Moi

Thank you for obtaining the accurate volume number. And thanks so much for your "convenience and courtesy" extended to the "smaller yet significant portion". There is a strong national tie to Project Mercury, since it was undertaken by the US, which in 1958 did not (and to this day, still in most of the aerospace industry, does not primarily) use metric units; therefore the English units should go first. That's the most authoritative way to obtain the correct value for the historical US space programs, as that was what was originally used in the design, and the metrics were/are a conversion extended as a courtesy. (NASA didn't switch officially to metric units until the 1970's.) We also have the Template:convert to maintain accurate unit conversions. JustinTime55 (talk) 16:28, 6 June 2012 (UTC)

Please see: Talk:Project Mercury#Capsule volume discrepancy, is this helpful? Soerfm (talk) 14:25, 4 April 2012 (UTC)

Not really, as the old value was determined to be inaccurate. JustinTime55 (talk) 16:28, 6 June 2012 (UTC)

Clarification needed

I have a problem understanding just what this sentence is trying to say:

"Twelve companies bid to build the Mercury spacecraft, an unusually high number for a $20 million contract, given the project's great prestige."

Exactly why would one expect fewer than 12 contractors to bid? The $20 million is in 1958 U.S. dollars, which doesn't give modern readers a good handle on it (would be equivalent to much more today.) And what is the assumed relationship of price to attraction? (One would assume it's positive.) And then, "given the project's great prestige" is thrown in at the end, which should attract more bidders. The use of "given" is confusing, and probably not what you intended? The phrase "given " is usually used to reinforce an expectation when used in such a sentence. Is this the essence of what you were trying to say?

"It was surprising that as many as 12 contractors bid, since , it was only worth $20 million; yet it had a great deal of prestige."

JustinTime55 (talk) 15:55, 6 June 2012 (UTC)

Cabin volume: source needed

The US Centennial of Flight Commission has a mistake on its Mercury page; the volume of the capsule could not possibly be 428.5 cubic feet, when the Apollo Command Module had only 218 cubic feet. (This is why we need verification!) I believe the 60. figure, because I tabulated a comparison with the others (Vostok for reference, is 63 cubic feet) but unfortunately I can't remember where I got that. Can someone help, please? JustinTime55 (talk) 21:27, 13 July 2012 (UTC)

Mission Profile

In the mission profile page it talks about how the orbital version needed a bigger rocket as compared to the sub-orbital version so that it can achieve a "higher altitude". This is misleading, the biggest reason why an orbital mission needs a more powerful rocket is the substantially higher speed needed to achieve orbit. 166.250.33.101 (talk) 04:44, 19 July 2012 (UTC)

Article insufficiently covers the Mercury spacecraft

This was the article a year ago, this is it now. A lot of information was removed for reasons not entirely clear to me, if it was removed because someone believed it was beyond the scope of the article than a page should have been created specifically for the Mercury spacecraft. Can we do anything to rectify this?--Craigboy (talk) 02:29, 29 September 2012 (UTC)

Revision July 2013

I have made a revision mostly based on

• Alexander, C. C.; Grimwood, J. M.; Swenson, L. S. (1966). This New Ocean: a History of Project Mercury (PDF). USA: NASA. ISBN 1934941875.
• Catchpole, John (2001). Project Mercury - NASA's First Manned Space Programme. Chichester, UK: Springer Praxis. ISBN 1-85233-406-1. {{cite book}}: Invalid |ref=harv (help)

I have deleted some information:

• claim in lead about planet Mercury (original research and not verified in body)
• claim about spacecraft being worn not ridden (no citation)
• claim about minor participants (no citation)
• claim that MJ-1 was proposed as a heat shield test (no citation)
• claim that MJ-2 was deemed unnecessary (no citation, contradicts budget constraint claim)

I reduced the information about T.J. O'Malley pushing the button to a footnote. I found a citation for the volume of the spacecraft, on the other hand, but it was 100 cubic feet and not 60 cubic feet. As requested, I have expanded the spacecraft section. I have also maximized the use of pictures. Finaly, I have deleted dead links and links overlapping Bibliography from External links section.

By the way, have you noticed that the kindle version of This New Ocean on Amazon includes an old version of the Misplaced Pages article? Soerfm (talk) 17:30, 9 July 2013 (UTC)

1. . United States government http://www.centennialofflight.gov/essay/SPACEFLIGHT/Mercury/SP17.htm. {{cite web}}: Missing or empty |title= (help)

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