Some Updates

Wow, it's been a while. But I've finally had an opportunity to fix the menus on the Field Guide. I use a program called GoLive which incorporates components that can be changed and then automatically copied to all the pages. When I add a new section all the menus have to reflect that. My GoLive crashed and I had to hunt down another copy to load into my computer. This happened last week, and I was able to finally update.

I also uploaded a 13th Anniversary graphic I actually made back in January. I'm sure you'll get the significance, and a little of the humor.

The big update is new images of Apollo 14 in the new display area at the Apollo-Saturn V Center at KSC. This was made last year, but I was unable to get over there until now. I notice I still have some work to do, some broken links, but you can check out the thumbnails.

UPDATE: I was able to fix many of the Apollo 14 links as well as missing images on the BP-30 page this morning. Still have a little work to do before I'm satisfied!

The big news is the return of the Gemini-Titan to KSCVC is imminent. The previous Titan suffered stress damage during the storms of '05, and was further damaged during removal. The remains are located in a storage yard just of KSC's Ransom Road. More on this and the new Titan II is an upcoming post.

Thanks for reading and supporting the Field Guide!

Discovery Lands at KSC

Discovery is ten minutes away from landing here at KSC as I start writing this. Through the walls of the HQ building I have heard the jet rumble of the Shuttle Training Aircraft, a modified Gulfstream 5, which flies the route before landing to visually check on weather conditions. Specially equipped with flight-deployable air breaks it can 'hang' and drop in the same landing approach as the orbiter. The shuttle itself drops faster and steeper than a normal aircraft, so training orbiter pilots demands a novel test vehicle.

Here I go outside. More in a minute....

BOOM! BOOM!

And by the time I'm back at my desk, the orbiter is wheels stopped on Runway 33. A beautiful sight, as this approach brought the orbiter almost directly over HQ. Orbiter and crew now safe and sound on Terra Frima.

A few things to know about these events (and there are only three more left, so listen up!):

The two sonic booms are produced by shock waves emanating from the orbiter nose and tail.

After the booms, you can hear the sound of the orbiter cutting through the air, and possibly the APUs (auxillary power units). Which is what the booms are: the compressed sound waves of all the soundthat would normally precede the orbiter (this is a very rudimentary explaination).

The STA follows a minute behind the orbiter.

While thousands of people may come to the center to watch a launch, only a few hundred are invited to the landing site. The viewing area is close enough that, if hypergolic fuel is leaking from a valve in the reaction control system, evacuation must be immediate. Busses are left running in case of this emergency. It is also why you see the first responders dressed in the full emergency suits with airpacks.

Technically speaking, the orbiter does not 'fly' or 'glide' until the last 30 seconds or so when the nose elevates above the horizontal.. That is when the wings start producing lift. Everything before that is a 'controlled descent', or what my friend Buzz Lightyear refers to as "Falling with style!"

The drag produced by the creation of lift also rapidly drops the airspeed, threatening a stall. The art is to hold off the stall until touchdown on the runway.

Runway 33 and Runway 15 are the same runway. The numbers indicate the approach heading, 33 toward the north at heading 330º, and 15 toward the south at heading 150º.

Time to end this and post while it is still timely. While launches are magnificent, landings are exquisite. I would almost prefer to watch a landing. Guess I'll have to figure out how to get a ride with the Navy for the future.

Like a Norwegian Blue: Beautiful Plumage

Working out of KSC I have been witness to many a launch. I know that launches at dusk or dawn can be particularly beautiful, as the light effects of the rising sun turn exhaust trails into works of art. Monday morning's launch of Discovery produced a display that surprised not only me but everyone at HQ I chatted with.



This beautiful display has some serious science behind it. You all know that as the orbiter ascends, it is traveling through increasingly rarefied atmosphere, until it reaches a near vacuum at orbital altitude. You also know that the Space Shuttle Main Engines (SSME) works off of Newton's First Law of Motion, and the action of the exhaust leaving the engine bell produces the reaction of the engine and shuttle moving away. The exhaust does not need to 'push' against anything to produce thrust. While this is true, the exhaust does push against something, the gasses of atmosphere. At sea level, atmospheric pressure helps constrain the exhaust into the familiar plume we see.

This Gemini-Titan launch shows an exhaust plume

constrained by sea level atmospheric pressure.

(Image by NASA)

As the rocket ascends, the thinner atmosphere allows the exhaust plume to expand. Engineers plan for this with the shape of the engine exhaust bell. Second-stage engine bells designed to work at high altitude are different than those on the first stage booster. Some engines are designed with an extendable collar that slips down at high altitude to take advantage of the expanding exhaust by increasing the length of the bell.

Notice different exhaust plume indications in this simplified SSME illustration.

(Image by Pratt and Whitney)

The SSMEs are designed to operate through the whole atmosphere, and optimized for mid altitudes after solid rocket booster seperation. When the orbiter reaches higher altitudes the exhaust rapidly expands. Although this lowers the efficiency of the SSME, the decreasing weight of the external tank and lack of atmospheric drag allow it to continue to thrust the shuttle to orbit. The video above (which appears to have been taken from near the US 1 highway in Titusville, FL) shows this expanding plume. Remember, this happens on every flight. What made this different was the darkness of the sky and the plume being illuminated by the sun just over the horizon. A beautiful confluence of technology and nature.

Aftermath of the launch plume in the light of sunrise.

(Picture by Jim Gerard)

New Computer, New Problem

I had to have my computer replaced due to a bad logic board (their explanation. I can see them in the back room hitting it with a rolled up newsparper, "Bad logic board! Bad! Bad!"). Anyway, they were able to transfer all my files over so I'm cool there, but some of my 'professional' software did not port over. So I'm down my web maintenance software and the Field Guide is needing help. Hopefully, I'll get my copy back this week and can get in and do the fixes I need to and some much needed updates. Until then, ignore any broken links and missing images, as the lists and locations should still come up. Thanks for your patience!

Spacecraft of the Week #17

Gemini VIII is this weeks featured spacecraft. Commanded by Neil Armstrong and piloted by David Scott, this spacecraft successfully launched to and docked with an Agena target vehicle in 1966.

Shortly after docking, the spacecraft began rolling on its long access access. The Agena was shut down, but the problem persisted. Scott noticed the ships fuel supply was dropping, indicating the problem was with the Gemini. The astronauts undocked the two spacecraft and began to move away.

However, just like an ice skater who accelerates her spin by bringing in her arms (the conservation of angular momentum), the Gemini began to rapidly roll, reaching a rate of one revolution per second. This threatened the astronauts who risked losing their visual acuity and or consciousness. Armstrong reacted quickly by disabling the Gemini's system of thrusters, and, using the backup reentry thrusters, regained control of the ship. This act would cut short their mission to just 10 hours.

Though many mission objectives remained unfulfilled, Armstrong's quick reaction and presence of mind would be a factor in his selection to command Americas first mission to the lunar surface. Launched this week in 1966, and now on display at the Armstrong Air and Space Museum in Wapakoneta, Ohio, the 17th Spacecraft of the Week, Gemini VIII.

Spacecraft of the Week #16

This weeks' honored spacecraft has traveled almost as much after its mission as during it. Apollo 9, nicknamed Gumdrop for its shape, was launched to low Earth orbit 41 years ago this week. During its stay in space, it rehearsed the upcoming lunar missions by docking to and extracting a Lunar Module, transferring crew, separating and going through the paces of a moon landing. After 10 days in orbit, it returned to Earth, splashing down in the Atlantic Ocean.

After its return, it was sent to the Johnson Space Center in Houston, Texas where engineers went over all parts of the spacecraft, checking and double checking to ensure craft and crew survivability of what was yet to come. After this inspection, it was placed on public display in the JSC Visitor Center.

Apollo 9 was later transferred to Jackson, Michigan and became the crown jewel of the collection at the Michigan Space and Science Center, located on the campus of Jackson Community College. While the collection was impressive, the center proved to costly and the college had to close it and remove the artifacts. Many of them, as well as curator Stewart Bailey, wound up at the Air Zoo in nearby Kalamazoo. Apollo 9 was a sweeter plum sought after by many. Since the spacecraft (as almost all flown spacecraft) is on loan from the Smithsonian National Air & Space Museum, they evaluated the requests and settled on San Diego.

The San Diego Air & Space Museum is located on the grounds of Balboa Park in the Ford Building, built as part of the California Pacific International Exposition, which was held in 1935 and 1936. There it was placed prominently in the entrance rotunda, sharing it's starring position with other aircraft manufactured in California (the Apollo spacecraft was built in Downey, California). The capsule is very accessible, forgoing the plexiglas cover seen on other Apollo capsules. It is displayed without it's hatch, which is sitting nearby.

So after 10 days in space and criss-crossing the US, Gumdrop finally rests about a 200 miles form where it was created. For that, and to celebrate its launch anniversary, Apollo 9 is this weeks' "Spacecraft of the Week'.

Spacecraft of the Week #15

Long past time for a new Spacecraft of the Week. I've missed several weeks due to job and family responsibilities. So in starting over anew we'll honor an anniversary this week (or, rather, last Saturday) and present the Mercury MA-6 spacecraft flown by Co. John Glenn on February 20, 1962, Friendship 7.

Continuing in the tradition established by Alan Shepard and Gus Grissom, Glenn included the numeral 7 as he chose Friendship as his craft's name. Although born of the Cold War, America's civilian space program was conducted in the name of peace and international goodwill. Friendship 7 finally enabled America to match the Soviet feat of orbiting a man around the Earth. But what was our successful first threatened to come to a fiery end.

First an aside. The Soviets knew as the Americans that a return to Earth from space would produce an incredible array of forces both on the spacecraft and its human occupant. Deceleration could be accomplished with parachutes and/or rockets, but these added weight to the spacecraft. Since the Soviet designers included an ejection seat to safely remove the cosmonaut during a launch mishap, they utilized this to allow the returning traveler to separate himself from his craft and descend by his own parachute, allowing the spacecraft to land with a force greater than a human could bare. Why do this? So that all aspects of flight and landing could occur safely within the confines of the mother country, where stories could be tightly controlled.

NASA, meanwhile, opted to use the vast oceans and its powerful naval forces to recover its astronauts and spacecraft. While water landing reduces the shock of impact, more cusioning was needed. So the capsule was designed with a mechanism to detach the protective heat shield and drop down extending a cylindrical skirt. This skirt would fill with air, and provide a cushion to the craft and it's rider. It was this detachable shield that created the drama.

As Glenn orbited the Earth, ground controllers at mission control in Cape Canaveral saw a disconcerting sight: the light indicating detachment of the shield was illuminated. This could prove catastrophic, as the heat shield protected the craft during re-entry. If detached, it would be torn away and the spaceship and its occupant would disintegrate in a meteoric fireball. A plan was developed, and the message was sent to Glenn to not eject the retro pack. They did not tell Glenn this was meant to hold the head shield in place, hopefully long enough to do its job. Glenn caught on fast and figured out it was something with the heat shield. The resulting reentry was especially spectacular as the retro pack burned away. It was later found the sensor was faulty and there was no danger from a deployed shield, but the experience led to new guidelines in crisis management and communication with the astronaut.

Currently, Friendship 7 is displayed in the National Air & Space Museum under the Wright Flyer. A layer of plexiglas protects it from the thousands of visitors daily. While the plexiglas makes photography difficult, it does allow guests to get very close with this historic craft. It's difficult to imagine a human being sitting inside this small vehicle and hurtling through the heavens. So we salute our first orbiting astronaut and the spacecraft in which he traveled as our Spacecraft of the Week.