Talk:Shuttle Carrier Aircraft

Weight

I'm not an aeronautical engineer, but it seems to me that the shuttle's weight would alone would counteract some of the lift generated by the SCA's flight, so that even if it added no drag, more of the plane's energy would have to go into keeping itself aloft instead of moving forward. The article I linked to (which isn't written by an aeronautical engineer, either) also says the weight is significant. Could you explain why you removed it? Thanks, Dave (talk) 16:20, August 10, 2005 (UTC)

I'd just had a quick discussion on sci.space.shuttle where I was told off for assuming it was weight not drag :-). Basically, the loaded weight of the Orbiter is about the same as the cargo+passengers weight on a normal 747, so the weight of the SCA plus Orbiter is about the same as the weight of a 747 taking off on a normal passenger flight. [1], which is written by an aeronautical engineer ;-)

As such, just lugging the Orbiter (and ignoring drag) would require no more fuel than flying normally, so in theory the SCA would have the same range... but it doesn't, and the difference is almost entirely due to drag (weight to a small degree, but also things like flying inefficiently). Shimgray 16:55, 10 August 2005 (UTC)

That makes sense, although it's hard to imagine the shuttle plus stabilizers etc. weighing less than three times as much as passengers, seats, and cargo. Maybe we should clarify in case it confuses someone else. Thanks for the quick response. Dave (talk) 16:57, August 10, 2005 (UTC)

Bear in mind that the SCAs have been gutted inside - they're missing all the seats, cabin furniture, and so forth. That weighs quite a bit. [2] quotes a quarter-million lbs of payload (presumably for a cargo variant), whereas the orbiter is about 240,000 lbs at takeoff (presumably similar or a little less on being ferried, as fuel and payload are missing, but tailcone &c added). So the numbers are pretty similar. Shimgray 17:06, 10 August 2005 (UTC)

I agree it's probably worth noting something about the payload issues ("weight no problem", basically), but I'm not best sure how to do it. Hmm. Shimgray 17:11, 10 August 2005 (UTC)

Fuel stats

Something looked odd with the fuel stats, so I looked up some of the info. There should be an infobox for this, but I didn't see it.

• Range 1000 nautical miles [3], = 1152 mi = 1852 km
• Fuel capacity of standard 747-100, 183,380 liters Boeing_747#Technical_data = 48,440 gal
• Length of standard 747-100, 70.7 m Boeing_747#Technical_data, = 232 ft

This gives fuel stats of 99 L/km and .0238 mile/gal. However, .0238 mpg is 125 ft/gal, about than half the plane length. Thus, the "1.5 times the length of the plane" part is not consistent with the other units. [4] Gimmetrow 23:55, 4 July 2006 (UTC)

Black Side Down

I know it seems somewhat silly, but it does seem to be a real joke - different reports give different wording (Attatch/Place/Mount Orbiter Here...), but photos certainly exist and have turned up in reputable works - I don't have my copy to hand, but some poking suggests, there's one in Dennis Jenkins' book.

[5] is another picture - note different style and wording. I suspect the joke has been recreated a couple of different times, possibly on different bits of hardware. Shimgray | talk | 19:29, 14 November 2006 (UTC)

• Yea, the Black Side Down part probably is a joke. The rest could just be overcautious warnings and such. The Place Orbiter Here image above is too small for me to read the lettering. -Fnlayson 05:50, 15 November 2006 (UTC)

PLACE ORBITER
HERE . . BLACK
SIDE DOWN

is a transcription, or close enough. Shimgray | talk | 18:55, 15 November 2006 (UTC)

Here's the image and entry in the article.

Orbiter Mount note image

• The rear mounting point on N905NA is labeled for the absent minded installer, with an instruction to "Attach Orbiter Here" — clarified by the precautionary warning "Black Side Down".

It was removed and I'm not sure it should be in there. -Fnlayson 19:43, 7 March 2007 (UTC)

For the record, I've just checked - it is indeed in Jenkins' Space Shuttle (photo on pp. 197, third edition, 2001), credited to Tony Landis - photographed with an orbiter attatched and the text blown up for clarity, though it's just about readable unmagnified:

CAUTION PLACE ORBITER
HERE BLACK SIDE DOWN
LEFTY LOOSY
RIGHTY TIGHTY

Same panel and (apparently) same strut, though possibly on the other aircraft or at a different point, so that's three sightings of the same gag, one cited in one of the definitive works. Just feel it best to make sure that if we do decide to remove it we don't do so under the misapprehension it's a hoax... Shimgray | talk | 23:42, 7 March 2007 (UTC)

Another image found, of the same style design and lettering as the one on wikipedia:

http://web2.jetphotos.net/viewphoto.php?id=5790 --Vox Rationis (Talk | contribs) 01:22, 8 April 2007 (UTC)

Also, I think although it does not directly contribute to the topic itself, it does significantly contribute to the general lack of intelligence that seems to occasionally spawn out of NASA, somewhat like the error is metric/imperial units, that caused the crashing of the Mars Climate Orbiter.--Vox Rationis (Talk | contribs) 01:36, 8 April 2007 (UTC)

-So is there any info that would help us get the "Black side down" joke? Does it refer to some old mistake made by NASA technicians? Please, my head is puzzled over this one! (From what i have understand, this sign REALLY exists on the plane, but i think those who wrote it on the plane did it as a joke...i mean, the pictures are real!) —Preceding unsigned comment added by 62.1.102.192 (talk • contribs)

• • Don't need info to get the black-side-down joke, just look at the orbiter...it's white on top, black on bottom. NASA technicians are actually quite known for their humor...I could show you other colorful additions on other NASA vehicles, but I would probably get hunted down and shot for it...ah, the joys and dangers of living in the Antelope Valley! AKRadecki^Speaketh 22:38, 31 October 2007 (UTC)

Looks like N911NA's joined the club. The bird was on static display at Wings Over Houston at EFD today. Saw the following on the side of the rear attach struts (on the outboard side of both of them):

Note: Place Orbiter
Here
Black Side Down

I can provide photos if necessary...and if someone tells me where/how to post them - ASFalcon13, 02:39 23 October 2010 (UTC)

why a plane?

Why do they use a plane for this? Why not a barge, for example? Wouldn't that be cheaper, or are there other concerns that influenced deciding to refit an airplane? 71.102.132.76 05:20, 13 August 2007 (UTC)

• Air lifting is quicker and simpler. Airlifting the Shuttle takes days vs weeks for other transport modes. Water is a corrosive environment. Not the best thing for expensive aerospace hardware, especially if not designed for it. Also, NASA has more control over things airlifting it themselves vs. getting a shipping company to ship it. Besides, it'd take some airlifting to get it to a seaport for water transport. -Fnlayson 05:37, 13 August 2007 (UTC)

Obliged. 10:08, 14 August 2007 (UTC)

(Very late answer) - because it is rather difficult to get a barge from Edwards Air Force Base, where the shuttle sometimes lands, and from Air Force Plant 42, where it was built, as these locations are in the Mojave Desert, far from any barge-able waterways. AKRadecki^Speaketh 22:37, 31 October 2007 (UTC)

Consider 2 new sections

consider 2 new sections, one for each aircraft. The joke wording, currently under trivia, is not so trivial and could be moved to the section about that aircraft. Archtrain 19:22, 9 September 2007 (UTC)

• The carrier mods are basically the same on both aircraft. I don't see the need for 2 sections that. -Fnlayson 00:27, 10 September 2007 (UTC)

Video previews

Please note that the large and overpowering video previews in this and other articles is currently being discussed at Wikipedia talk:WikiProject Aircraft#Media content?. Input invited; if you don't participate, don't complain when consensus is achieved without you... AKRadecki^Speaketh 22:44, 31 October 2007 (UTC)

Piggy-back flying

An editor has questioned how the shuttle could be launched in flight from the SCA when it is on top. He/she has since added a source which confirms that this did indeed happen. However, I've not been able to find a sourced aerodynamic exclamation for how it is done. I think it would be good to have a brief summary of how this occured during the Approach and Landing Tests (ALT). Also, launching piggy-back aircraft is not unique, and dates back to the purpose-built Short Mayo Composite, and possibly to even before. - BillCJ (talk) 02:21, 13 February 2008 (UTC)

It's not a terribly crazy thing. I suspect the editor is thinking of a drop-type release, when in fact the 747 dove away from the shuttle after release. Quote: "Accompanied by five T-38 chase planes, the 747 flew a racetrack pattern above the lakebed. The release was scheduled for 8:30 a.m., but higher-than-normal air temperatures slowed the climb to the release altitude. At 8:48 a.m., Fulton nosed the 747 SCA into a shallow dive, and Haise radioed "The Enterprise is set; thanks for the lift." Haise then pushed the separation button, firing seven explosive bolts. The Enterprise seemed to pop off the back of the 747. Fulton then put the 747 into a descending left turn, while Haise pitched the Enterprise to the right." Source:[6].--ABQCat (talk) 10:42, 13 February 2008 (UTC)

Cruising Speed unit problems

So, even [NASA's page on the SCA] says that the cruising speed is Mach 0.6, or 250 knots. This is impossible. Mach 0.6 is 397 knots, and 250 knots is Mach 0.38. Given that it's a 747, I'm going to presume that the mach 0.6 is correct, and I edited that section of the article to reflect that. However, it's difficult to really state categorically that's the situation, since our source is obviously wrong as well. Anyone have a better source? burnte (talk) 04:42, 22 September 2008 (UTC)

Definitely confusing. The actual line states "Airspeed limits with, and without an orbiter:" 250 knots or Mach 0.6. It's possible that 250 knots is the limit with the orbiter, and Mach 0.6 is the limit without it. Both figures seem very slow, so I agree we need to find some other sources. - BillCJ (talk) 04:56, 22 September 2008 (UTC)

I provided a source for the data that was there. Your 397 knots speed looks reasonable but should rounded. It could use a source or footnote explaining the calculation. -Fnlayson (talk) 04:58, 22 September 2008 (UTC)

BillJC, I read it that the cruising speed was the same for both, as the orbiter is fairly aerodynamic (relative to a brick). Further, the fact they give different units tells me it's all the same speed regardless of load.

Fnlayson, I realize you gave a source, but my point was only that all our sources seem to conflict with themselves. :) The calculation is fairly simple, Mach 0.6 is 0.6 times the speed of sound, which is 661 knots. 0.6 * 661 equals about 397. If you wish to round it to 400 I have no qulams with that. The fact remains, our sources are inaccurate in one way or another. Either it's Mach 0.6, or it's 250 knots, but I really can't believe it cruses at 250 knots. burnte (talk) 08:58, 22 September 2008 (UTC)

• I'm aware how the Mach number works. The speed of sound depends on the air density which varies with altitude. Is that speed at sea level, 15,000 feet or other? -Fnlayson (talk) 12:45, 22 September 2008 (UTC)

Mach 0.6 at 35,000 feet is roughly 350 knots. It's quite possible "250" is a typo. - BillCJ (talk) 13:43, 22 September 2008 (UTC)

Or not. I found a back issue of Airpower magazine from May 1992. On page 24, in a photo caption, it states: "Due to airspeed limitations of the 747's struts and dual tip fins, SCA ferry flights are flown at 250 knots at altitudes between 13,000 and 17,000 feet." Now if we can just figure out where the Mach 0.6 came from . . . - BillCJ (talk) 14:22, 22 September 2008 (UTC)

I looked it up in the SCA Flight Manual SCA(N)-1 page 5-4. Limitations and Specifications configuration 3 (with shuttle loaded) Flaps Retracted Vmo 250KIAS and .6 Mach. Colputt (talk) 20:34, 4 March 2010 (UTC)

Photoshopped image?

Orbiter Mount note reminding technicians how to connect the orbiter to the transport.

This image has been removed by an unregistered user saying it is photoshopped. Does anyone know this for sure?--PremKudva^Talk 05:18, 19 June 2009 (UTC)

It's real. Look at the section "Black Side Down" above, as well as searching for attach on the following page on the NASA website: NASA’s Innovators and Unsung Heroes. -- kenb215 talk 08:17, 19 June 2009 (UTC)

Just out of interest, I (zeeeter) took the photo of the "in-joke" about the orbiter mount, while I attended the Edwards AFB open day. It's legit. Anyone need the original photograph for pixel by pixel analysis from which you can easily see any edits, along with several other photos I took of the vehicle and event are welcome to contact me directly. That plus the fact that this has clearly been photographed elsewhere should put this to bed hopefully! —Preceding unsigned comment added by Zeeeter (talk • contribs) 04:34, 14 November 2009 (UTC)

Shuttle retirement

I can't find any information about what will happen to the SCAs when the shuttle program ends. I found a mention of a proposal to use them as spare parts for the Stratospheric Observatory for Infrared Astronomy, but the source also says the plan fell through due to uncertainty in the shuttle retirement date. -- Cyrius|✎ 06:10, 13 September 2009 (UTC)