NASA Armstrong Flight Research Center operates a number of aircraft out of Building 703 at Palmdale airport. Among those, two airliners from yesteryear – a Boeing 747SP and a Douglas DC-8 – that found a new life as research aircraft can be found.
Last year, I had a chance to fly on the larger one of those – the 747SP which serves as an airborne observatory – during its deployment to New Zealand. Earlier this year, I was fortunate enough to have been able to cover the smaller and older DC-8 that NASA uses to study the atmosphere among other things.
Continue reading to join me onboard the mission I joined in April and to see how NASA uses the former Alitalia airplane to advance science.
Egress Training & Mission Briefing Before Boarding the Aircraft
The flight started for me the day before we actually took off as that’s when I visited NASA Armstrong Building 703 not only to see the aircraft based there up close but also to take the mandatory egress training.
Just like when I flew on SOFIA, the egress training consisted of a video explaining the safety features of the DC-8 – many of which were nothing like you would see on a regular airliner – and of a presentation filling in more details about the topics covered in the video.
On the day of the actual flight, all of the crew members gathered in the briefing room about two hours before the scheduled departure time to go over the details of the flight. The Mission Director took a roll call, the researchers gave updates about the status of their instruments and their research plans, and the cockpit crew provided critical information related to the flight itself.
Once the briefing was over, I was escorted out of the building and onto the apron, quickly snapping a photo of SOFIA that was being prepared for its night flight before walking over to the DC-8 which was parked a bit further.
I walked around the aircraft a bit before climbing up the stairs and entering the cabin – still not believing that I was actually about to fly on the DC-8.
Third Time the Charm: Take-Off from Runway 07
Not long after I boarded the aircraft and secured my luggage for take-off, I joined the two pilots and the flight engineer in the cockpit. Around 2:30PM, they got their headsets on and started going through the pre-flight checklist.
The DC-8’s four engines were brought to life one by one – starting with the inner port side engine, continuing with the inner and outer starboard ones, and finishing with the outer port side engine.
With the engines running, the pilots started their pre-taxi checklist and one of them asked the ATC for a permission to taxi. Once we were cleared to do so – via taxiways Sierra, Echo, and Papa to runway 22 – the pilots made sure all the ground equipment was out of our way and put the aircraft into motion.
While making our way to runway 22, they asked the ATC if we could take off from the closer runway 25 instead – a request that was granted right away. By the time we reached runway 25 end, though, there was a significant tailwind. And so, since we had plenty of time to spare before our planned take-off time, the pilots decided to ask the ATC if we could take off from the other end of the runway.
The request was once again granted without any issues and so, at 3:08PM, we took off from runway 07 into the sunny Californian skies.
About thirty minutes after take-off, we reached the Pacific coast. Besides the vast Pacific Ocean in front of us, we could also see Long Beach airport on our right.
It was there – the pilots kindly pointed out to me – that exactly 50 years ago, in 1969, the NASA DC-8 was manufactured. Of course, when it first came out of the factory, it was a standard airliner – originally delivered to Alitalia before being bought by Braniff International Airways – and not the flying laboratory that it is today.
Soon after, as we continued climbing, we flew over Santa Catalina Island and a part of the science crew started collecting data. Then, once we reached an altitude of 34,000 feet, the HALO operators were given permission to lase – more about that later in the article, though.
I stayed in the cockpit for some more minutes – observing the pilots and flight engineer in action – before going into the cabin to learn more about the aircraft and the science that was being done onboard.
Nothing Like an Airliner: Exploring the NASA DC-8
Overall, just like with SOFIA, there was very little to remind the people onboard that the aircraft once used to haul passengers on scheduled flights around the world.
The seats – while similar to US domestic first class ones – were all equipped with shoulder harnesses. Furthermore, mixed between the rows of seats were equipment racks with state-of-the-art instruments and other specialized workstations.
One of the only things that gave a hint about the aircraft’s previous life and its original operator Alitalia was the “no smoking” and “fasten your seatbelt” sign featuring not only English but also Italian text.
Right outside the cockpit, the aircraft’s navigator station could be found. And behind that – in front of R1 door – there was a “standing room only” rack with screens showing our position on the map and other flight information.
Continuing, there was the Mission Director (MD) station from where the whole operation was controlled. It was the MD’s job to oversee the mission as a whole and to liaise between the science teams in the cabin and the pilots in the cockpit. Throughout the flight, the MD asked the pilots to make adjustments to speed, heading, and altitude based on the requests made by the instrument operators.
I loved the fact that whatever area of the MD station was not covered with buttons, switches, screens, and other equipment was covered with stickers depicting the aircraft’s previous missions and cities it visited among other things instead.
Two “safety techs” responsible for preparing the cabin for take-off and landing, as well as for keeping it safe throughout the flight were onboard the flight as well – one in the front of the cabin and one in the back.
At the very back of the aircraft, there was a small counter with some snacks that the crew brought and a cooler box with water as well. While the aircraft wasn’t equipped with a refrigerator, there was a microwave so that the crew could heat up their meals on what often are long and cold flights.
Of course, while wondering around the cabin, I could not skip stopping by one of the DC-8’s large windows every now and then to look at the wings and engines. While the aircraft was originally delivered to Alitalia with four Pratt & Whitney JT3D engines, those were replaced with the more fuel-efficient CFM56-2s in 1986.
DAWN, HALO, and Other Instruments: The Heart of the Mission
Besides exploring the aircraft itself, I also had a chance to spend some time talking with Kris who was the mission lead on the science side of the flight as well as other researchers from NASA Langley about the mission we were flying as well as the instruments that were onboard to help carry out that mission.
Our flight was the first in a series of flights primarily aimed at testing DAWN (Doppler Aerosol Wind Lidar) that uses laser shot at particles such as dust and salt in the air to profile wind.
The scientists also plan to use the data gathered by DAWN to validate data provided by ADM Aeolus, a European satellite which – just like DAWN – uses doppler lidar for profiling wind. Kris mentioned that we were able to get about an hour of overlap with the path of the satellite orbiting the Earth.
Another instrument that was a critical part of the mission’s payload was HALO – High Altitude Lidar Observatory – which according to NASA “uses Differential Absorption Lidar and High Spectral Resolution Lidar to profile atmospheric aerosols and water vapor” and helps the scientists better understand the data provided by DAWN.
Other instruments onboard included POS AV – a system designed for georeferencing of airborne sensor data, DLH which uses laser to measure the amount of water vapor in the air around the aircraft, and a pair of instruments using probes mounted on the exterior of the aircraft to analyze air’s carbon monoxide, carbon dioxide, and methane content.
The last of the above can help scientists understand characteristics of fires and was “just piggy backing” on our flight to fine-tune the instruments according to their operator. The instruments will be used more extensively during the DC-8s next mission which will collect data on wildfires in Idaho and Kansas. By that time, though, there will be many more probes sticking out of the aircraft.
It’s Not Just Computer Screens: Launching Dropsondes
It was fascinating learning about all of the instruments above. At the same time, though, given that they were all essentially sensors gathering data and displaying it on screens in a form very difficult to understand for a non-expert like me, it was also very abstract.
In that regard, there was one thing that was much more visual and exciting to watch in action than all of the other instruments, the dropsonde system.
Located at the back of the aircraft across from HALO, it allowed the researchers to drop weather sondes out of the aircraft through a metal chute. Mark, who was operating the system, was kind enough to explain to me how it worked.
First, he had to place the sondes in an instrument designed to get their GPS initialized. That had to be done because the aircraft acts like a Faraday cage and thus the GPS signal is weak in the cabin itself.
Then, when it was time to launch a sonde, he would take it out of that instrument, open the chute’s valve – the only thing separating the cabin from the skies outside – drop the sonde through the “hole” in the fuselage, and close the valve.
All of that had to be done in one smooth motion to ensure that the device would not lose connection between being taken out of the instrument and dropped out of the aircraft.
Once the dropsonde was out of the aircraft, Mark would check its status through a monitoring system that could be accessed through the aircraft’s intranet and announce:
Sonde is in the air and telemetry’s good.
A few minutes later, the sonde would splash into the ocean.
Throughout the flight, we launched ten dropsondes. Most of those were standard weather sondes recording atmospheric pressure and temperature, but a couple of them were experimental ones equipped with a pitot tube and modified to measure vertical wind speed.
Simply Enjoying the DC-8
I spent the rest of the flight – the time not spent learning about the instruments or chatting with one of the crew members – simply enjoying my time onboard the classic aircraft type that I never thought I would have the chance to fly on.
Besides just relaxing in my seat, I of course spent a lot of time looking out of the window – especially during the sunset.
I was also able to visit the cockpit during the blue hour.
Landing Back in Palmdale
Around midnight, the MD informed the HALO team that they would have to start securing their instrument as soon as we reached MALIT, a waypoint just off the coast of California, since from there we would be flying directly to Palmdale and crossing a corridor of aircraft departing Los Angeles airport for Asia.
Ten minutes later, the HALO laser was shut down, and another few minutes later, the instrument was completely secured and ready for landing.
Then, the rest of the cabin was prepared for landing. I, once again, attached my bag to one of the seats so that it would not move around the cabin during landing and made my way to the jumpseat for landing.
Just like seeing the Aurora Australis on my SOFIA flight, seeing the countless lights of Los Angeles from the DC-8’s cockpit as we were descending towards Palmdale is one of the things that I will never forget and that will stay vividly in my memory for a long time.
Once we were low enough, the pilots contacted the air traffic control with the following words:
Joshua Approach, NASA 817, we’d like to cancel IFR.
Continuing the flight under VFR, at 00:27AM, they lowered the landing gear. A minute later, they set the flaps to full and turned the autopilot off in preparation for landing.
We landed on Palmdale airport’s runway 25 at 00:34AM after almost nine-and-a-half hours in the air. After vacating the runway through taxiway J, we taxied for a few minutes before reaching the apron in front of NASA Armstrong Building 703 at 00:45AM.
Once we came to a full stop, the engines were shut down, and some of the crew members started getting off the aircraft while others remained onboard a bit longer to finish their work.
I was among the first to get off, and after taking a couple more photos of the DC-8, I walked through Building 703, returned my NASA badge, and headed back to my hotel – once again completely awed by the work NASA is doing to advance our understanding of the world we live in.
To end this article, I would like to thank the public affairs team at NASA for arranging this opportunity, as well as everyone onboard the DC-8 for patiently explaining to me details of the research they were doing as well as the instruments that were onboard and so on.