Green Chile Chapter 691
of the Experimental Aircraft Association

Education and support for general aviation

Recording Flights of Fancy

By Vivek Saxena

I have always naturally gravitated toward the technical side of aviation, and since my day job as a physicist involves grappling with problems of a more theoretical/mathematical nature, flight training has given me the opportunity to revisit and more deeply appreciate basic physics, engineering and aerodynamics. Between May and July of 2022, I took a series of introductory flights at a few flight schools in New Jersey with no plan of pursuing flight training. After all, it seemed very expensive and quite unaffordable unless one were to pace it out (resulting in protracted delays, lack of proficiency, and higher costs in the long term). I began gathering information and pestering my father (a rite of passage for all my technical pursuits) to partake in the knowhow. An important turning point for me was the Los Alamos Airport Open House on July 23, 2022, where I met Will Fox and David Young and other friends from EAA 691. Until that day, I had not been exposed to the world of experimental aviation and I was struck with awe to see all the complex airplanes that people had built with their bare hands.

It took me another year to develop enough conviction to actually get started with flight lessons, after some hiccups. Despite the sensible advice of flying multiple times in the week to retain proficiency, my primary occupation as a physicist does not leave much time for non-physics activities (mostly a personal lifestyle choice) and flight lessons are expensive at least here on the East Coast, so I am taking the slow approach and flying once a week, with occasional breaks. Will and David have very generously provided advice, suggestions and much needed critical analysis from a distance throughout this endeavor, and I am extremely grateful for my (mostly) long-distance association with EAA 691.

As I tend to be a slow learner and learning to fly involves acquiring and honing various motor skills and appreciating as well as anticipating the dynamics of the airplane, it struck me early on in my flight school research that it might be extremely beneficial to record my flight lessons for review. In this article, I will share details of my setup which I hope will be of use to others.

First of all, if you record your flight lessons with cockpit audio, it is important that your CFI be comfortable with it. Many flight schools and instructors are justifiably wary of this, as publicity often leads to problems. Also, the instructor should not feel inhibited in their instructional criticism of the student just because they are being recorded, so it definitely helps to have an honest conversation about the goals and expectations on the ground. My personal goal was to use these videos strictly for review and document my flight lesson journey, and I felt reviewing all the comments from the instructor (beyond the venerable “More right rudder!”) would be very helpful especially if I were not flying regularly enough; I never desired to put them in the public domain. I have been fortunate so far to have instructors who have permitted this. But if you do decide to put your aviation videos online, the AOPA has some useful advice [1, 2].

Recording requires a camera, and GoPro cameras seem to be popular choices. One does not need the most expensive or the fanciest camera in my view, but it is useful to have a camera with an inbuilt GPS and sensors to record some basic telemetry data. I currently use a GoPro Hero 10. (Note that the newest GoPro model, the Hero 12 has no GPS.) Where should you mount the camera? This boils down to a personal choice – see this video by cub pilot Joe Costanza for some pointers [3]. If you would like to use a single camera that also records cockpit (intercom) audio like I do, the best place to put it is inside the cockpit, preferably on the ceiling of the cockpit. GoPro cameras come with plastic mounts with double-sided 3M adhesive tape. These prove to be quite sturdy and can be easily replaced. Also, your camera is less likely to fly away into the wilderness if you mount it inside.

If you can afford to have additional cameras and the flight school/instructor allow mounting them externally (using mounts that do not run the risk of breaking off and impairing control surfaces in flight) this can be helpful for judging landing approaches – see [4, 5] for some worthy examples. But these external cameras will naturally not record or be linked to the same inflight cockpit audio track, which will have to be carefully synchronized and re-embedded using video-editing software later.

An important point is that the camera setup should not interfere with piloting or flight instruction. If the camera stops recording, or malfunctions or misbehaves in any way, the pilots should not be distracted by it. I think it works best if the camera is simply switched on sometime before one begins with the checklist, and then switched off when the flight is complete and the airplane is secured. Any video editing should only be done on the ground. Suction cup mounts can fail in flight and fall, and if the camera is hooked up to audio cables connecting to an aviation headset, this can be a dangerous distraction especially in single pilot operations.

To record cockpit audio, one needs an interface cable and adapter that effectively sits in between the PJ jack on the airplane and the aviation headset and splits off the audio feed to the GoPro. This is a 3-pronged audio splitting cable: one end is a USB-C connector that connects to to the GoPro’s USB-C port, the second end is a female PJ-068 (or M642/5-1) connector for the aviation headset’s PJ-068 male microphone plug, and the third is a male PJ-068 connector that goes into the cockpit PJ-068 female microphone jack. The PJ-055 (or M642/4-1) headphone cable from the aviation headset connects directly to the cockpit PJ-055 female headphone jack. I use a cable+adapter from NflightCam [6]. A 6 ft cable seems adequate for an airplane like a Cessna 172. Note that most GA airplanes have mono audio channels, so the video produced may have audio only in the the left or right channel. This is quite normal and can potentially be fixed using software.

The audio cable and adapter are the most crucial items in the setup. Out of an abundance of caution, in single pilot operations, I recommend using an audio port from a passenger’s PJ jack to connect to the GoPro, to isolate the pilot’s audio channel from the GoPro setup. Alternatively, one could consider keeping a second pair of headphones and/or a handheld radio, just to have a redundant failsafe for radio communication in the rare scenario of a defective audio cable/connector disconnecting the pilot’s microphone from the airplane intercom.

So this 3 piece setup consisting of (1) a GoPro camera, (2) an aviation headset cable + microphone adapter, and (3) plastic slider mounts with double-sided tape, are all that one needs to get started with video + inflight cockpit audio (ATC) recording.

However, unsurprisingly, there are some engineering limitations of this minimal setup. First of all, almost all GoPro cameras are known to overheat and shut down, especially when recording at 4K @ 30 frames per second for more than 40-45 minutes. To partially alleviate this, one can direct the cockpit air vent at the GoPro to keep it cool, but I found this to be inadequate. Secondly, battery life on the GoPro is poor, especially when recording at such high resolutions. There are a few tricks one can adopt like turning off wireless connectivity between the GoPro and your cellphone, reducing the resolution to 1080p (1920×1080), tweaking sharpness settings, etc. But 4K video really looks much better and it is hard to downsize once you’re used to it!

This is a picture of my setup.

One thing that helps the most with battery life (and heating) is to not have the battery at all, keep the battery door open, and instead use an external USB-C power charger to power the camera. I use an old Anker PowerCore 26,800 mAh as my rear seat passenger, along with a long USB cable. Sporty’s FlightGear Backup Battery [7] seems to be a popular choice among flight instructors, and can also be used to keep one’s iPad charged.

However, for whatever reason, the factory installed GoPro operating system (OS) does not permit the use of the external microphone adapter (needed to connect your aviation headset) with the battery removed, and this requires flashing the OS with a “GoPro Labs” experimental OS, which is perhaps only fitting given that this is an article for an EAA newsletter. (This is not nearly as dramatic as “rooting” your cellphone with a custom OS – there is no voiding of the warranty, and you can safely go back to the factory OS if you so wish.) For those interested, I provide some details in a footnote [8].

To circumvent overheating – which remained an issue for me despite keeping the battery enclosure open and vacant, and caused some rare perfect landings to never be documented in the annals of history – I found it helpful to mount a small USB powered fan to the camera. There are some inexpensive ways of doing this but I eventually chose CAMCooLER [9], a 3D printed enclosure for the GoPro Hero 10 consisting of a USB fan, manufactured by Roy Potter in Arizona. (A cheaper alternative is to purchase a $15 USB fan and use a rubber band to attach it to the camera, but this arrangement is flimsy and can get dislodged in flight. The CAMCooLER housing does provide some protection to the camera if it were to fall off.)

Finally, one also needs to use a neutral density filter to account for the stroboscopic effect [10] from the propeller. I use an ND8 filter sold by Nflightcam [11].

The telemetry data on GoPro recordings can be extracted and overlaid on the videos using a telemetry extractor software program such as Telemetry Overlay [12], created by an independent software developer, Juan Irache, based in Barcelona. This can be useful for instructional purposes, although the data is not as reliable as what aircraft instruments report (and notably, there is
no tachometer available). Moreover, this data is corrupted by quantization noise. (For example, the attitude indicator gauge sourced from the GoPro data would often show me as making an inverted landing, or a 90 degree banking turn while taxiing – exponential progress that should surely impress my instructors.) After extensive experimentation and discussions with Juan, we concluded that the telemetry data is affected by the camera being mounted in an inverted posture, particularly because of the orientation of the GPS antenna on the camera. This can be partially overcome by relying instead on a recording of the cockpit instruments, provided the camera is angled at them. It is worth noting that Telemetry Overlay can accept alternative sources for flight data, such as AHRS data from Garmin devices. The instructional value of such data may be questionable, but I have always been interested in flight data acquisition so it seems only natural to push this further.

Everything you need to get started with GoPro video recording can now be acquired in one shot as a single packaged kit from Nflightcam [13] – this includes a camera and all the accessories mentioned above except the USB battery pack and the external fan, which must be purchased separately from other sources. The entire setup described here should cost about $560. Jaymo, a member of Nflightcam’s technical staff, recently produced a video with some suggestions about audio and video recording and gave me permission to share it [14].

So much for the setup. How has it contributed to my flight training? It has given me the confidence of being able to review and go over my mistakes, and stay honest about my progress. It also helps to have a targeted set of questions for my instructor, especially when I am still pondering at the end of a 2-3 hour long lesson and don’t have every question articulated for a debrief. It has also helped me isolate weak spots or things that need fine tuning in training. But it obviously does not compensate for flying infrequently, and no amount of ground analysis can replace the important experiences and skills developed in the air.

I end this article by sharing a few resources that I have found useful in my flight training. There is no shortage of engaging books on aviation – see [15] for some suggestions. I highly recommend using Google Earth (as opposed to Google Maps) for exploring unfamiliar areas while on the ground, and scouting for emergency landing sites, especially to prepare for engine failure after takeoff. (I have recently found it useful even to spot landmarks around my home airport to help with pattern work, and I anticipate it will be beneficial also for planning longer trips.) Finally, Youtube has a rich (and ever expanding) collection of instructional videos about flight maneuvers and techniques, although one does have to be a bit discerning to avoid some silly (and occasionally downright wrong) physics ideas.

About the author: Vivek is an “at large” member of EAA 691. He is a theoretical high-energy physicist with a background in physics and electrical engineering. He is enthusiastic about tailwheel flying, backcountry/bush flying, and experimental aircraft in general.

[1] For The Record: What’s Not To `Like’ : Sharing Your Videos Online:
[2] What Not to Record When Flying:
[3] Safely Mounting GoPro and Insta 360 Cameras on your plane, on strut, tail, rudder and cowling:
[4] Chase View of Tailwheel & Footwork Required to keep a Taildragger straight down the runway:
[5] Slipping an Airplane, Descend like an elevator while having fun and shortening your approach:
[6] NflightCam Aviation Audio Cable + Power Cable for GoPro:
[7] Sporty’s FlightGear iPad Backup Battery:
[8] Steps to enable concurrent use of external battery pack with mic adapter on a GoPro:
1. Back up and format your SD card.
2. Download the GoPro Labs firmware on your computer and decompress it to your SD card (follow these instructions to install it on your GoPro). This lets you configure a bunch of settings by encoding them in a QR code
which the camera can then read (by simply hovering it over the QR code).
3. Visit, and pick your favorite settings. But be sure to add the line!MTUSB=1 as an “Additional Command”.
4. Hover your GoPro on the QR code so generated. The camera will beep and a tiny picture of the QR code will appear on the LCD display with a check next to it. This signals a successful setup.
See and and for more details.
[9] CAMCooLER 9Ten11&12:
[10] Stroboscopic effect:
[11] Nflightcam Propeller Filter for GoPro Hero 9, Hero 10, Hero 11 and Hero 12:
[12] Telemetry Overlay:
[13] Nflightcam Content Creator and Student Pilot GoPro Package:
[14] Audio recording instructions by Jaymo, pilot and tech support member at Nflightcam:
[15] Suggested reading:
•Barry Schiff, “An Illustrated Guide to Flying,”
•Rod Machado, “How To Fly An Airplane,”
•Rod Machado, “Private/Commercial Pilot Handbook,”
•Rick Durden, “The Thinking Pilot’s Flight Manual,”
•Rich Stowell, “Learn To Turn,”
•Rich Stowell, “The Light Airplane Pilot’s Guide to Stall/Spin Awareness,”
Rich Stowell, “Emergency Maneuver Training,”
•Dale Crane, “A Pilot’s Guide To Aircraft And Their Systems,”
David A. Lombardo, “Aircraft Systems: Understanding Your Airplane,”
•H.C. Skip Smith, “The Illustrated Guide to Aerodynamics,”
•ASA, “The Pilot’s Manual – Ground School and Flight School”: and
• manuals on airplane engines, and VFR communications: