One Direction, NASA, Patricia Lynn, and modern all weather attack.

You should probably mute this, but play “name that plane” and spot the non-T-38 plane in the video.

[youtube https://www.youtube.com/watch?v=Jwgf3wmiA04]

That’s the WB-57F  Canberra, used by NASA for high altitude atmospheric research. It was originally used by the USAF to collect atmospheric samples during nuclear testing. Collecting samples of radioactive particles after a nuclear blast, physicists can tell a great deal about how effective a device was. We collected samples both of our own devices, and those of the Soviet Union, and indeed everyone else’s.

[youtube https://www.youtube.com/watch?v=HGmHf0UYyps]

The WB-57 was derived from the RB-57, which was something of a poor man’s alternative to the U-2. A basic B-57 bomber was converted with vastly larger wings and upgraded powerplants to give it a much higher operational ceiling. Unfortunately, as the U-2 discovered in May of 1960, the SA-2 Guideline had an even higher ceiling.

The basic B-57 itself was built by Martin, being derived from the British English Electric Canberra bomber.

The first major variant operational with the USAF, the B-57B, served in Vietnam as a day/night interdiction/strike aircraft, and even flew some strikes against North Vietnam in the early years of the war. Increasing air defenses there meant it was soon withdrawn from use up north, but it soldiered on for a few more years providing air support in South Vietnam, eventually being replaced by newer tactical aircraft.

To find targets for those tactical aircraft meant aerial reconnaissance, and a lot of it, particularly against the NVA’s logistical trail, the Ho Chi Mihn Trail.  A lot of RF-101 Voodoo and RF-4 Phantom sorties were flown, but results, particularly at night, were less than great. And so Project Patricia Lynn was started.  A handful of RB-57Es were deployed to use infra-red cameras locate targets. It was very effective, with some estimates that 80% of the usable aerial reconnaissance came from Patricia Lynn.

Martin B-57E-MA 55-4237 Da Nang AB South Vietnam 3/4 front view at Da Nang AB, South Vietnam, in January 1964. Aircraft was originally B-57E (S/N 55-4264). This aircraft was lost on Oct. 25, 1968. (U.S. Air Force photo)

The adaptability and flexibility of the B-57 also lead to a couple of experiments with using sensors such as Low Light Level Television and infrared line scanners to allow the crew to see targets at night in real time, rather than having to wait for IR film to be developed.

That impressive real time capability lead to the ugly, but impressive B-57G. With LLTV, IR and a laser rangefinder/designator built in, the B-57G was the first truly effective precision night attack jet. It was the first jet to have a built in capability to self designate targets for laser guided bombs at night. The cutting edge technology meant they were maintenance nightmares, and had poor availability rates, but when they worked, they showed just how effective night attack sensors and precision guided weapons could be.

https://upload.wikimedia.org/wikipedia/commons/c/c2/190th_Tactical_Reconnaissance_Group_B-57G_Canberras_1973.jpg

Switching back to the big wing WB-57 for a bit, let’s talk about networked warfare for a bit. More and more, we rely on datalink networks to provide a picture of the battlefield. But that raises to problems. Not all datalinks are compatible, and most are line of sight only. That lead to the development of BACN, the Battlefield Airborne Communications Node. BACN is both a relay and a translator, allowing various networks to work together. And since line of sight increases with altitude, it was first deployed aboard the WB-57, and operationally used in Afghanistan in 2012.

The WB-57s have returned to NASA, and a third has recently been added to the fleet. Not bad for a design the British first flew in 1949.

Post Crash Fire

Surviving an airplane crash is actually more common than you’d think. The problem is, there’s often a post crash fire, which is often quite a bit harder to survive.  A major portion of aviation safety engineering is geared toward providing survivors just a bit more time to exit the aircraft before it is consumed by flames.

[youtube https://www.youtube.com/watch?v=Dgu5RKrIqS0]

[youtube https://www.youtube.com/watch?v=FqYVkIWacCE]

 

Indeed, this has been a long standing goal of NASA and its predecessor NACA.

[youtube https://www.youtube.com/watch?v=c4MwwrMLDoY]

The C-82 Packet was not a terribly successful aircraft, and only about 223 were built. Redesigned and with the R-2800 swapped out for the more powerful R-4360, it would emerge as the C-119 Flying Boxcar, a far more successful design that would soldier on from the 1950s into the 1970s, with over 1100 built.  According to NASA around 50 airframes, mostly C-82 but also a couple of C-46 Commandoes, were expended in the testing.

Poor Roamy doesn’t get to blow up airplanes.

X-37B Launch Video, and A Co-author quoted in the New York Times

Yesterday the Air Force hush-hush X-37B space plane successfully launched from Cape Canaveral.

[youtube https://www.youtube.com/watch?v=HJCEVFgswjw]

In addition to whatever the Air Force has the X-37B doing, they allowed NASA to piggy-back an experiment aboard.

NASA is also taking advantage of this X-37B flight to test how almost 100 materials react to the harsh conditions of space, like the barrage of radiation and swings of temperature the craft will experience while passing between the day and night sides of the Earth for at least 200 days.

“It’s just sitting there and letting the environment hit it,” said Miria Finckenor, a materials engineer at NASA’s Marshall Space Flight Center in Huntsville, Ala. She is the principal investigator for the experiment, which is housed in the space plane’s cargo bay.

The materials to be tested include thermal coatings to keep spacecraft components within a certain range of temperatures, clear materials under consideration for lighter windows on NASA’s Orion crew capsule and ink to make sure that markings on parts do not fade away.

NASA previously tested more than 4,000 samples outside the International Space Station, but it is difficult to carve out time during spacewalks to set up and retrieve the experiments. “This opportunity presented itself, and we just needed to take advantage of it,” Ms. Finckenor said.

I’m just a simple grunt. Would you believe that I actually know three, count ‘em, three honest to goodness rocket scientists?

Boeing X-53 Active Aerolastic Wing

 

NASA F/A-18 as the X-53 AAW.
NASA F/A-18 as the X-53 AAW.

Today in 2006, was the first flight of the Boeing X-53 Active Aeroelastic Wing. While I’m aware of the Active Aeroelastic Wing (AAW) program and aware of the role the F/A-18 plays as NASA, including it’s roles as an airborne laboratory and as a chase aircraft, I had no idea that the AAW program had formally received an “X” designation:

 12/11/2006 – WRIGHT-PATTERSON AIR FORCE BASE, Ohio  — Air Force Research Laboratory researchers recently received word that the Active Aeroelastic Wing (AAW) flight demonstrator has been assigned the Mission Design Series number X-53. The designation makes it the first successful X plane initiated within the Air Vehicles Directorate since the X-24 lifting body concept, which was later employed on the Space Shuttle.

The AAW program is control technology that uses wing flex (in the AAW program case of 5 degrees) in conjunction with conventional flying surfaces (ailerons, flaps and leading edge slats) to give increased control moments. This would mean less drag when these surfaces are moved at high speed, decreased structural weight. In a way the AAW comes full circle in aviation. The Wright Flyer used wing warping in much the same manner.

The Wright Flyer used aerolastic "wing warping" as control services in flight.
The Wright Flyer used aerolastic “wing warping” as control services in flight.

As mentioned, the X-53 is a pre-production F/A-18 Hornet and the structural modifications to the aircraft are:

The wings from NASA’s now-retired F/A-18 #840, formerly used in the High-Alpha Research Vehicle (HARV) project, were modified for the AAW flight research project and installed on the AAW test aircraft. Several of the existing wing skin panels along the wing box section of the wing just ahead of the trailing-edge flaps and ailerons were replaced with thinner, more flexible skin panels and structure, similar to the prototype F/A-18 wings.
Original F-18 wing panels were comparatively light and flexible. During early F-18 flight tests, however, the wings were observed to be too flexible at high speeds for the ailerons to provide the specified roll rates. This was because the high aerodynamic forces against a deflected aileron would cause the wing to deflect in the opposite direction.
In addition, the F/A-18’s leading-edge flap was divided into separate inboard and outboard segments, and additional actuators were added to operate the outboard leading-edge flaps separately from the inboard leading-edge surfaces. By using the outboard leading-edge flap and the aileron to twist the wing, the aerodynamic force on the twisted wing provided the roll forces desired. With AAW control technology, a flexible wing will now have a positive control benefit rather than a negative one.
In addition to the wing modifications, a new research flight control computer was developed for the AAW test aircraft, and extensive research instrumentation, including more than 350 strain gauges, was installed on each wing.

NASA’s 853, the X-53 AAW is one of the oldest F/A-18 Hornets still flying. This model in particular is one of the early production aircraft. Here’s photo walkaround of the X-53:

EC01-0076-1

Technicians tend to No. 853 inside one of the sprawling hangars at NASA Dryden. The plane, shown here getting routine maintenance, carries evidence of past research projects. Some of the instruments and devices are left in place because they may be used again.
Technicians tend to No. 853 inside one of the sprawling hangars at NASA Dryden. The plane, shown here getting routine maintenance, carries evidence of past research projects. Some of the instruments and devices are left in place because they may be used again.

 

No. 853’s nose is home to an array of navigation and guidance gear, along with research equipment like the Airborne Research Test System. ARTS  is a computer that allows engineers to quickly and easily test new software and equipment without installing a dedicated computer for each project. That gray box at the bottom of the nose is an ARTS.
No. 853’s nose is home to an array of navigation and guidance gear, along with research equipment like the Airborne Research Test System. ARTS is a computer that allows engineers to quickly and easily test new software and equipment without installing a dedicated computer for each project. That gray box at the bottom of the nose is an ARTS.
nasaf1812
These tubes protruding from the wing spars of No. 853 once were connected to the static pressure sensors on the wing. The sensors measure air pressure over the top of the wing to help determine the airflow during various maneuvers. The lift generated by the wing is dependent on the flow of air around the wing. Engineers can better understand the effects of various tests such as the wing warping if they have a precise way to measure the air pressure over the wing
nasaf1814_0
No. 853’s left wing details the longest history of the plane’s role as a test mule. It bears little resemblance, aside from its shape, to the sleek, smooth wing the plane had when it left the factory. The wing is dotted with sensors, equipment and remnants of the epoxy-like material engineers use to hold everything in place.
nasaf1815_0
To accurately measure and monitor the wings during the project, sensors along the wing measured air pressure as well as strain on the wing structure.
nasaf1816
The blue box houses the transmitter and receiver that work in conjunction with the reflectors to measure wing strain. All of those sensors and other equipment require miles of wire, and No. 853 is packed with them.
nasaf1819_0
Small reflectors are placed along the wing. Light emitted from a transmitter along the spine of the airplane is bounced off the reflector back to the box, allowing engineers to precisely measure wing strain in three dimensions.
nasaf1822
NASA researchers found wing warping could produce adequate roll rates at transonic and supersonic speeds. The software control laws that manage warping to control roll offer several advantages over traditional roll control, including reduced drag and improved maneuverability. And perhaps counter intuitively, a lighter structure can be used because aerodynamic forces on the wing can be more closely controlled, reducing strain
nasaf1825
Aside from NASA’s test equipment, the X-53’s cockpit doesn’t differ that much from the production Hornet.

You can learn a bit more about the X-53’s Wikipedia page here and from NASA itself at the X-53 fact sheet.

It’s an interesting program with future technoloigcal applications to both civil and military airplanes.

NASA 853 in flight.
NASA 853 in flight.
NASA 853 with the gear down turns over Armstrong Flight Research Center.
NASA 853 with the gear down turns over Armstrong Flight Research Center.

“To seperate the real from the imagined through flight” – Hugh Dryden

The X-31

Spill hit an estate sale this week, and came away with a nice little gem.

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpa1/v/t34.0-12/10721492_10204597455074329_1869747615_n.jpg?oh=bf04777c305c60b94ee56b5c20b5997b&oe=543AAF3B&__gda__=1413198038_e905bc46f7e8ff75d11b2c51e478cc1b

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t34.0-12/10721341_10204597456554366_2120987638_n.jpg?oh=4fde91112a8c0010c023921cbc6b70d5&oe=543A7018&__gda__=1413117193_2f03273d7364755ad1a18d5125982ff1

This coin contains metal from the X-31 aircraft.

How did they get the metal from the aircraft? Glad you asked.

The use of digital fly-by-wire controls in high performance aircraft, covered by Spill here, 2, 3, 4, 5, meant that unconventional flight controls could be used on planes to maneuver in ways not previously possible. In particular, thrust vectoring could be used to control aircraft at very high angles of attack.

A joint US and German test program conceived and built the Rockwell/MBB X-31 research plane to explore this use of DFBW control in conjunction with high angles of attack and thrust vectoring.

File:Rockwell-MBB X-31 vectorpaddles.jpg

X-31 in flight. Notice the three “paddles” used to vector the thrust.

Two were built, and a highly successful test program showed the X-31 was capable of maneuvers that were then astonishing. Since it was purely a research aircraft, it was quite small, had a very small fuel load (typically, only 4100 pounds) at take off had a thrust-to-weight ratio of 1:1, which meant it could accelerate vertically right off the runway.

After several years and hundreds of test flights, one of the two X-31s had its pitot tube replaced by a Kiel tube. The pitot tube us the pointy stick pointing out of the nose of the jet. It measures the dynamic pressure of the air. Between it and a static air pressure sensor, the pitot system provided air data to the flight control computer to determine speed and altitude.

Remember, in a DFBW system, the pilot doesn’t control the airplane directly. He uses the flight controls to tell the computer what he wants the plane to do. The computer uses those imputs, along with air data from the pitot system, and attitude data, to determine which controls should be deflected, and how much.

Obviously, if the air data was corrupted, the computer would provide corrupted control deflections.

One of the most common failure modes for pitot tubes is icing. Moisture from clouds or humidity freezes on the pitot tube, constricting the flow of air through the tube, which makes the computer think it is going faster than it is. To combat this, most pitot tubes have an electrical heater, just like the rear defroster on your car. The normal pitot tube on the X-31 was replaced by Kiel tube, which gave more accurate air data at high angles of attack. But it didn’t have a heater. Given that the flight test rules for the program prohibited flying the X-31 in known icing conditions, this wasn’t thought to be a significant hazard.

Of course, Murphy gets a vote. The engineers knew there was no pitot heat. The pilot didn’t.  And of course, the X-31 encountered pitot icing. Not immediate, but gradual accumulation of ice led to a steady degradation of airflow, and hence data. And that led to instability, as the flight computer tried to make the plane do things that it didn’t want to do.  The X-31 exectuted an uncontrolled pitch-up, and as soon as the pilot realized he had no control, he safely ejected.

The loss of the X-31 is unusual in that it was very carefully documented. It took place almost directly over the airfield, and was being tracked by powerful cameras on the ground.

Here’s the short version:

[youtube https://www.youtube.com/watch?v=WIUtUrKMw2k]

If you’re interested, a 40 minute video investigates the chain of errors that led to the mishap. It can be found here.

And here’s a brief history of the program.

Outstanding Engineering in the development of the Apollo Program Lunar Lander

The Apollo program that lead to the landings on the moon was a stunning engineering and program management feat. It simply boggles the mind the complexity of the mission, and the countless details that went into the development of the hardware, the software* and techniques and procedures that lead to Neil Armstrong’s one small step for man.

In some ways, the most complicated piece of equipment on the entire Saturn V/Apollo stack was the Lunar Module, or LM. Designed and built by Grumman, it was America’s first true spacecraft, in that it would never fly through the atmosphere, instead only in space. Without the need for aerodynamics, it had a truly unusual appearance, sometimes leading it to be called “the bug” or “the spider.” It was a two stage rocket that had to be capable of autonomous navigation from lunar orbit to the surface. It also had to serve as a base camp for astronauts for up to 72 hours, and then it had to be capable of ascending from the moon’s surface to lunar orbit and again rendezvousing with the Command Service Module under its own navigation.  It had to have its own power supply, be able to operate both in a shirt sleeve environment for the crew as well as depressurized and open to the vacuum of the moon’s surface. It had not one, but two hatches, to allow both for docking with the CSM, and to allow the astronauts to explore the surface of the moon. It was also the largest manned spacecraft built at the time.

It was, incredibly, designed well before anyone knew if rendezvous in low earth orbit was technically feasible, let alone in lunar orbit.

  Grumman, in close cooperation with North American Aviation and NASA built this incredible craft. I’m sure you’ve all seen the movie Apollo 13 where the LM served as a lifeboat to return the crew safely to home, stressing the LM in ways it was never intended to be used. To say that the engineers of Grumman built an incredible ship is an understatement.  Some of the finest engineering talent in the world focused on getting the LM just right.

Incredibly, well into the development of the LM, with most of the configuration well established, and production ready to begin, no one ever gave serious consideration to how the astronauts were supposed to get down from the LM to the lunar surface, and back inside after hopping around the moon.

Lander no ladder

Yes. That’s an astronaut holding a knotted rope. No ladder. Grumman and NASA actually even looked at a complicated block and tackle system by which astronauts would hoist themselves down and up. It took a while before it occurred to anyone to simply fasten a ladder from which Neil and 11 others could make a great leap for mankind.

 

*During the development of Apollo, when the engineers spoke of software, they actually generally meant the flight rules, switchology, and cockpit procedures the astronauts would use on the hardware. Software was already coined as a term for computer code in other areas, but doesn’t appear to have been in vogue in the program office for computer programming.

Drowning in microgravity

Roamy posted a while back on the aborted spacewalk of Italian astronaut Luca Parmitano aboard the ISS.

Here’s an update to that story:

Luca Parmitano wrote in his online blog, posted Tuesday, that he could no longer see as the water sloshed around in his helmet outside the International Space Station.

“But worse than that, the water covers my nose – a really awful sensation that I make worse by my vain attempts to move the water by shaking my head,” the former test pilot wrote. “By now, the upper part of the helmet is full of water and I can’t even be sure that the next time I breathe I will fill my lungs with air and not liquid.”

Parmitano, 36, a major in the Italian Air Force making just his second spacewalk, wasn’t sure which direction to head to reach the station’s hatch. He tried to contact his spacewalking partner, American Christopher Cassidy, and Mission Control. Their voices grew faint, and no one could hear him.

“I’m alone. I frantically think of a plan. It’s vital that I get inside as quickly as possible,” he wrote.

Parmitano realized Cassidy – making his way back to the air lock by a different route – could come get him. “But how much time do I have? It’s impossible to know,” he said.

If you’ve ever come close to drowning, it’s a terrifying experience. Kudos to Major Parmitano for keeping his cool under extraordinary circumstances.

“Space is a harsh, inhospitable frontier and we are explorers, not colonisers,” he wrote. “The skills of our engineers and the technology surrounding us make things appear simple when they are not, and perhaps we forget this sometimes.

“Better not to forget.”

Wiser words. When Roamy kindly hosted me at the Marshall Space Flight Center, one of the things that struck me was just how many different ways the harsh environment of space could find myriad ways of killing you.