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Photo of Curiosity during descent phase, taken from orbit. This shot is amazing all by itself.
Curiosity is powered by a Pu-238 oxide thermoelectric generator. The Multi-Mission Radiosiotope Thermoelectric Generator, MMRTG, has an output of 2000 watts thermal and 100-120 watts electric. The MMRTG unit sits in the aft end of the rover enclosed by a finned heat exchanger.
Wow. This guy has style.
Spring 1980. I arrived at the airport at 6:30 on a calm morning along the front range of Colorado. Judson Flying Service was open for business with a modest fleet of Cessnas. Two 150’s, a fairly new 152, a 172, a 182, and a 210. I had 48 hours of time logged in preparation for my checkride.
My flight instructor, Fred, had signed me off for the checkride after my successful short and long solo cross country flights. We had practiced a bit on the short and soft field landings. I loved landings. If there is a time that you feel that the machine is an extension of your limbs, it is during the landing phase.
I nearly had to cancel the checkride. I had contracted a bout of conjunctivitis following a visit to the opthamologist. My eyes had cleared up sufficiently so I decided to proceed with the flight test. Scheduling with the FAA designated examiner was hit and miss so I didn’t want to miss my slot.
The examiner gave me a destination- Yuma, Colorado. My job was to put together a flight plan and call it in the flight service station (FSS). While on the line with the FSS, I got a thorough weather briefing. I plotted a course based on radio navigation stations (VORTAC), estimated time enroute and fuel consumption, identified several alternate airports enroute, and collected the various radio frequencies and ground references for dead reckoning.
We were ready. We walked out to the airplane where I did a thorough preflight check and answered questions on aerodynamics. Satisfied, the examiner and I strapped into the Cessna 150 and began the engine startup procedure. He pulled a few tricks including leaving his belt unconnected and didn’t completely latch his door. Having the door pop open on takeoff is startling for everyone, pilot included.
The 4-cylinder horizontally opposed Lycoming engine lit up after a few turns like it always did. After checking to see that the oil pressure was in the green and that the fuel gauges indicated what we observed by visual inspection, we taxied to the runup area on the taxiway near the start of runway 29. Pointing the nose toward the approach airspace of 29, we went through the pre-takeoff checklist. Breakers look fine. Radio check. Adjust the mixture. Run the engine up to 1600 rpm and alternately switch off the two magnetos one at a time to look for function and for a worrisome loss in rpms. Verify that flight controls are operating properly and that the flaps are set to the recommended position.
It’s settled. The machine wants to fly. We’re going aviating. A serious scan for incoming traffic and, noting none, we radio to what traffic there might be that we intend to depart on runway two-niner and leave the traffic area to the east.
I release the foot brakes and taxi onto the runway. After we turn onto the active runway the throttle goes to the firewall and the engine promptly revs up to full power with that righteous unmuffled roar from the engine. We’re a little on the heavy side with two adult men on board, but N63110 still accelerates smartly down the runway.
As we begin to accelerate with my left hand on the yoke and my right hand on the throttle, I’m busy keeping the nosewheel on the centerline of the runway with the rudder pedals while glancing at the airspeed indicator. The airspeed indicator seemed sluggish. As we get close to what appeared to be rotation speed the airspeed indicator still didn’t register any airspeed.
To actually launch into the air without airspeed indication would be a huge mistake. Not only would it be terribly dangerous, but I would fail the checkride if we survived the ride around the patch and the landing ordeal ahead. So, I pulled back the throttle and applied heavy braking. We taxied off the active and made for the shop. No available 150’s that morning, so the checkride was canceled.
Turns out that some bugs had nested inside the pitot tube overnight and blocked it.
Flying very much depends on making sure that the airflow moves over the wings above a minimum velocity and within a range of acceptable angles. Without airspeed readings, the approach to landing would be very sketchy. The landing phase requires that the pilot slows the airplane so that a glide is established to the ground. The glide speed is easily controlled by adjusting the pitch of the airplane. In a normal landing it is nose down. The sketchy part is that the airplane is close to stall speed during this phase and so any kind of loss of controllability or lift near the ground will have dire consequences.
A week later I arrived at the airport at 6:30 on a cool windy morning along the front range. This brisk morning the winds were out of the west at 12 kts gusting to 14-16 kts straight down runway 29 with a broken ceiling at about 9000 ft above sea level, or 4000 ft above the ground. The winds were squirrely for a 150 but not bad enough to cancel.
I repeated the flight planning of a week ago and we walked out to the airplane and strapped in. The FAA examiner had a hood with him for use in simulated instrument conditions. I looked at the hood with some dread. Performance anxiety, really. But I had a fair amount of hood time and had always done fine.
We take off and point the nose to the east and climb to 7500 ft MSL. The winds were strong at altitude and turbulence was making the flight somewhat strenuous. I had precise flying to do with a strong silent-type examiner. After I lock onto the VORTAC and verify the station’s Morse code identifier, the examiner hands me the hood and announces that I just flew into a cloud.
Being prepared for this I put on the hood which resembles a welding helmet except it has a narrow blinders protruding forward to block the view outside the airplane but still allow view of the instruments. It is used routinely for simulated instrument flying.
I tell the examiner that the flight to our destination is aborted and that we were returning to the airport by doing a 180 degree turn. The idea is to turn around promptly to the reciprocal heading to exit the clouds most expeditiously.
Being a cocky 23 year old male I smartly roll the airplane into a left 45 degree bank and try to intercept the reciprocal heading. While executing this and while fighting turbulence I overshot the heading. So I roll the airplane into a right 45 degree bank and try to intercept it again. Again I overshot it. By this time some dizziness had set in to complicate my cockpit chores while I try to remember what the desired heading was and get back to my designated altitude.
With the excessively steep turns and the turbulence I had managed to lose control of the aircraft under simulated instrument conditions. I didn’t realize it at the time, but I also had vertigo. As I wrestled with the flood of seemingly contradictory instrument readings, a tumbling gyro, and distracting g-forces I continued to try to wrestle the machine into level flight.
The examiner just sat there. Legally he was just a passenger. I was the pilot in command.
My mind was overloaded with fear. My brain was trying to reconcile the what my inner ear was telling it with what the turn and bank indicator, altimeter, and airspeed indicator were telling me. I had fallen into a classic and fatal combination. It’s called the “graveyard spiral” or the spiraling power dive. I should have done a gentle standard rate turn and avoided the g-forces and higher skill needed to maneuver like that.
When it became obvious that I wasn’t going to recover, the examiner took the yoke and corrected the turn as he told me to take off the hood. As I removed the hood I saw in front of me a great circular corn field with center pivot irrigation slowly wetting down the field. We were perhaps 500 ft above the ground and still in a dive.
Grateful that the examiner had left something for me to do to save the flight, I retarded the power and carefully pulled out of the dive. The airspeed needle was was adjacent to the red zone.
I climbed back to a cruise altitude and flew back to homebase. The examiner wanted to do some other test items, but I was so humiliated that I wanted to get back on the ground. Once back in the traffic pattern I set up a short soft field approach and executed the best landing I had ever done. The wheels kissed the ground and came to a stop without wasting even a foot of ground. The pride was wounded but the skills were there.
A week later and after a humbling hour of remedial hood time, I retook the flight test and easily passed it. The same examiner signed my ticket. He never chided me or said anything to humiliate me. I think he knew that a major life lesson had happened and was glad that it was under supervision. I have never forgotten the corn field that should have had a smoking crater in it on a blustery day in June, 1980. When I close my eyes I can still see it.
A company called Atair Aerospace offers an autonomous parachute system comprised of self-guided chutes that, according to the site, are able to avoid one another in multiple drop scenarios. Thus the need for “flocking algorithms”. The company claims a ~57 m accuracy in some of its parachute dropping systems. The company also makes an Inertial Measuring Unit that combines input from GPS, inertial, and barometric sensors, all in a package the size of a Buffalo wing.
Interesting quote from the Daily Kos–
> For all of our bad-assity—all our guns and nukes and soldiers and cops and black helicopters and warrantless surveillance and militias and tough talk and the fact that our private citizenry is armed to the teeth with every type of firepower imaginable, we sure scare easily. Half the stuff over which we tremble is a figment of our own overactive imaginations. But one thing is as real as it is backwards: we fear our government, but our government does not fear .
> Our media is so afraid to offend anyone that they go out of their way to give both sides of an issue equal weight, even if one of those sides is either factually incorrect or batshit crazy…thus slowing down our progress as a country even more.
Ah, yeah. Pretty much.
Pity Brian the Bat. This innocent winged creature just wanted a place to rest. Unfortunately, he chose to rest upon the liquid fuel tank of the Space Shuttle Discovery prior to liftoff. Brian was last seen clinging to the shuttle as it cleared the tower during launch into the night sky.
It is not known how far Brian rode the spacecraft. NASA speculates that Brian was blown into the exhaust plume shortly after clearing the launch tower and fried to a crisp. The acoustic energy on the exterior of the shuttle during launch is around 149 db. The little bugger was surely stunned by the noise.
The Brian Bat foundation has been started in its honor (wink wink, nod nod). I’m sure that all people of goodwill will contribute to memory of this hapless fellow.
This is one of the better videos showing details of the technology. I wonder what the stall speed of this thing is. It would be interesting to see what airspeed or pitch attitude limitations he might have when he releases his ‘chute.
The fellows in the second video are experimenting with a different configuration. I suspect they will eventually rediscover the phenomenon of flutter if pitch divergence doesn’t get them first.
Check out this link to photos from the Baikonur Cosmodrome. See how cozy the Soyuz Capsule is.
Thanks to Les for the link.
(Credit: AP Photo)
Here is something you don’t see every day. Two Shuttles are now sitting locked and loaded for the upcoming Hubble repair mission. Think of all of the contained energy waiting to spring out.
Van’s Aircraft indicates they are in the final phases of flight testing their new entry, the RV-12, into the Light Sport Aircraft (LSA) category. This is a new regulatory category of aircraft that has resulted from some new thinking about what is necessary and sufficient in terms of the regulation of homebuild light aircraft. The new category relaxes certain restraints on operators of homebuilt aircraft.
The new regulatory requirements found in the LSA are welcome to those trying to enjoy aviation on a budget. The video below shows an interview with Dick VanGrunsven, founder of Van’s Aircraft.
August 2, 2008. Kwajalein Atoll. In the third failure in the fledgeling commercial SpaceX launch program, a Falcon 1 lifter failed to achieve orbit shortly after liftoff. The payload package consisted of two NASA packages, one DoD package, and one package for Celestis, Inc. The Celestis payload consisted of ca 208 vials of the cremated remains of customers who paid to have their ashes delivered into orbit.
Among those disappointed customers were the late actor James Doohan (“Scotty” from Star Trek) and astronaut Gordon Cooper. Curiously, this was their second successive space disaster together. The package of remains previously fell to earth and landed in the White Sands area in May of 2007 following an earlier failure of a launch vehicle.
Wende Doohan, James Doohan’s widow, told the Associated Press news agency her late husband “probably wished he could have stayed [in orbit]”. -BBC
Internet mogul Elon Musk said, “It was obviously a big disappointment not to reach orbit”. Musk is a founder of SpaceX and PayPal. According to SpaceX, the failure occured when a thrust transient during first stage shutdown caused it to recontact the second stage soon after separation. This contact perturbation caused the vehicle to fail to reach orbit.
“Laddy! Would ya be needin’ a little somethun’ to wash that doon with?”
-Cmdr Montgomery Scott