If you have shopped for LED landing lights, nav/strobes, or beacons for your Cessna or Piper, you have run into a wall of acronyms — TSO, PMA, STC — and a price gap that makes no sense until someone explains it. A “meets FAA standards” LED bulb shows up online for $40. A certified assembly from us costs several hundred. Same light, right?
Not even close. And the difference is not markup — it is whether the part is legal to fly behind, who is allowed to install it, and who carries the liability if it interferes with your avionics at the worst possible moment.
Here is the plain-English version, from someone who sells these kits every day and flies behind them.
The one sentence that clears up most of the confusion
Aircraft parts are approved to be manufactured under standards such as PMA and TSO, and approved to be installed under STCs, Advisory Circulars, field approvals, and other data acceptable to the Administrator.
Almost every mistake owners make comes from blurring those two things. A part can be beautifully manufactured to an FAA standard and still not be approved to bolt onto your specific airplane. Building and installing are two separate approvals. Keep them separate in your head and the rest falls into place.
The three acronyms, decoded
TSO — Technical Standard Order
A TSO is a minimum FAA performance standard. TSO authorization lets a manufacturer build a part to that standard. It validates performance — color, intensity, and coverage. Position lights are built to TSO-C30; anti-collision lights to TSO-C96.
What a TSO does not do is approve installation on your aircraft. It certifies that the light performs the way the FAA requires. It says nothing about how that light mounts to your wingtip.
That gap is what AC 20-41A fills. It’s the FAA’s accepted means for substituting one TSO’d light for a functionally similar TSO’d light already approved on your aircraft. Swap a TSO-C30 position light or a TSO-C96 anti-collision light for another unit built to the same TSO, and AC 20-41A supports the installation, provided the connected electrical systems aren’t adversely affected and any change in capability is reflected in the flight manual.
PMA — Parts Manufacturer Approval
A PMA is production approval to manufacture a replacement part. Like a TSO, it covers building the part — not how it mounts on the airplane.
STC — Supplemental Type Certificate
An STC approves the design change itself — how the part installs on a specific aircraft. Critically, an STC includes the installation instructions your A&P follows, and it can cover both TSO and PMA parts. A TSO’d part installed under an STC is the gold standard: performance is proven and the installation is approved.
What this jargon actually means for you
Every WAT (Whelen Aerospace Technologies) and AeroLEDs certified assembly we sell is approved and can replace a like-for-like assembly on your aircraft. Some carry a TSO, some a PMA, some an STC, some all three. Both manufacturers have taken the guesswork out of it and provided exactly the certifications you need — and when a manufacturer’s approval covers your installation, that paperwork comes with the part at no additional cost. You are not paying extra for a certificate on a like-for-like swap. It is already handled.
There is one exception, and it is the exception that trips people up: when you change how the fixture mounts to the aircraft.
The nuance that costs people money: “changing the mounting”
If you have to add something to the aircraft to attach the new assembly — a bracket, an adapter plate, a modified housing — that is a change to the type design, and the manufacturer’s like-for-like approval no longer covers you. Something has to bridge the gap between the certified light and your specific airframe.
That is precisely what an Aero-Mach Wilco STC does. Where WAT and AeroLEDs certify the light, our STC certifies the installation on the aircraft that needs added bracketry — the piece the manufacturer’s like-for-like approval was never meant to cover. Our STCs are engineered, tested, and approved so your A&P can install the kit, sign it off, and move on — no field approval, no guesswork. Yes, that engineering and testing raises the cost, because certifying the bracketry that attaches the lights to the airframe is real, expensive work. What you get for it is a factory look and a clean installation instead of the “arts and crafts” project a DIY adapter turns into.
And here is the part worth underlining: when we quote “our” STC, we are quoting a complete package — the lights, the brackets or adapters, and the STC approval paperwork, together. It is not a certificate you bolt onto parts you source elsewhere. It is everything your mechanic needs to do the job right, in one kit.
On the Cessna side, most 100- and 200-series wingtips need our adapter plates, so the STC does real work. On many Piper wingtips the modern LED footprint (like the Whelen Orion 650) matches the legacy housing directly — but the wiring still changes when the strobe power supply comes out, so it is still an A&P job. Which brings us to the question owners ask most.
Who is actually allowed to install it?
This is where owners get real value, because the answer determines whether you can do the work yourself or whether it has to go through a mechanic. It comes down to one thing: does the installation change the wiring or the structure?
Owner / operator — preventive maintenance. A plug-and-play LED landing or taxi light that involves no wiring change and no structural change is preventive maintenance under FAR Part 43, Appendix A(c). You replace it and you log it. AC 20-41A backs a TSO-for-TSO substitution when the connections do not change. The moment you change the wiring, you leave this lane.
A&P mechanic — STC installation. Pulse/wig-wag controllers, combined taxi-and-landing units, and nav/strobe/beacon upgrades all change the wiring — the strobe power supply is removed entirely. These are installed per the STC, and the A&P signs the return to service. WAT, AeroLEDs, and the Seaton MaxPulse all ship with the STC/PMA paperwork in the box.
A&P with Inspection Authorization (IA) — deviation or required inspection. If you deviate from the STC, you need new approved data — a field approval on FAA Form 337, signed off by an A&P who holds Inspection Authorization. A required inspection also takes the IA.
One more detail worth knowing: under FAR 43.3(d), an owner may do the hands-on work under an A&P’s direct supervision — but the A&P (or an IA on a major alteration) still makes the return-to-service entry. Always confirm the classification with your shop before you start; your mechanic makes the final call on how a given installation is logged.
“But I found one on Amazon for $40…”
Let’s talk about that light. The FAA does not charge a manufacturer for certification. What costs money is the engineering, testing, and validation required to earn it. When a part skips that work, the savings come out of your compliance and your liability — not out of thin air. Proceed at your own risk, and know what you are actually risking.
No TSO means no compliance data. A non-TSO’d LED replacement may not meet FAA color or intensity requirements, and without a data package, neither you nor your installer can demonstrate compliance if anyone ever asks. The liability lands 100% on the installer.
“Meets TSO standards” is not the same as having a TSO. If a seller claims their part meets the TSO but holds no actual approval, ask for the test data. TSO approval is free — the testing is not. The absence of a TSO usually means no data was ever submitted to the FAA.
Clear-lens swaps create unapproved parts. Some products require you to replace your original red and green lenses with clear lenses so a white LED can shine through. Doing that voids the prior FAA TSO approval on the original assembly. That light is now an unapproved part for night flight — full stop. Unapproved replacement LED bulbs are also where a large share of avionics interference complaints originate.
What certification actually proves. A genuine certification program tests the things that fail airplanes: thermal performance inside an enclosed housing, vibration and shock resistance, EMI/EMC interference with your avionics, and long-term reliability and failure modes. If a product were truly designed and tested to aviation standards, there is very little reason for the manufacturer not to pursue certification.
So why does certified LED lighting cost more?
Because in certified aviation you are not just buying a light. You are buying an engineered upgrade for a specific aircraft. The price reflects the STC engineering and certification, the aircraft-specific brackets, wiring, and hardware, the testing and documentation and support behind it, and the small production volumes compared to the automotive world. Certified aircraft lighting has to recover its engineering and certification costs across a fleet a tiny fraction the size of the car market. That is the honest reason for the number on the invoice.
The Aero-Mach Wilco STC kits: what “bridging the gap” looks like
When a manufacturer’s like-for-like approval covers your airplane, you are done — the paperwork is in the box at no extra cost. When your wingtip needs added bracketry, our STC kits do the bridging. Two of the most common are below. Each is quoted as a complete package: lights, brackets or adapters, and the STC approval paperwork, together.
Cessna Nav/Strobe STC Kit
This kit is for models with original Cessna wingtips. STOL or other aftermarket wingtips require a deviation and field approval.
Covered models (14V):
150L, 150M, 152, 172L, 172M, 172N, 172Q, 172R, 172S, 172RG, 177B, 177RG, 180H, 180J, 180K, 182N, 182P, 182Q, 182R, 182S, 182T, T182T, R182, A185F, 185E, U206F, U206G, TU206F, TU206G, 210K, T210K, 210L, T210L, 210M, T210M, 210N, T210N, P210N, 210R, T210R, P210R
| Item | Part number |
| Two adapter plates | — |
| Green nav/strobe — OR6501G | 01-0790725-01 |
| Red nav/strobe — OR6501R | 01-0790725-02 |
| Tail light — 71554-12 | 01-0771554-12 |
| Optional upgrade — OR5001V combo tail (position + anti-collision) | 01-0771774V01 (+$200) |
Beechcraft Bonanza & Baron Nav/Strobe STC Kit
This kit is for models with the larger Beechcraft wingtip lenses used on 1974-and-after Bonanzas and Barons.
Covered models (14V):
F33A, G36, V35B, 36, A36, A36TC, B36TC, 95-B55, 95-B55A, 95-B55B (T-42), G58, E55, E55A, 58, 58P, 58TC
| Item | Detail |
| Two adapter plates | — |
| Two LED nav/strobe lights | — |
| One LED tail strobe light | — |
| Optional upgrade — five-light kit (+$450) | Adds 2 LED recognition lights + 2 Reclens kits |
Don’t see your model, or flying a 28V aircraft or an aftermarket wingtip? That is exactly what a quick consultation sorts out — we will confirm applicability before you order.
To be clear about where the cost goes: these STC kits carry the price they do because of the added expense of certifying the bracketry that attaches the lights to your airframe — not because of markup on the lights. And when we quote our STC, that quote is the whole package: the lights, the brackets or adapters, and the approval paperwork your mechanic signs behind. One kit, one price, nothing left for you to source or certify on your own.
Common questions from Cessna and Piper owners
Do I need an STC to install an LED landing light?
Not always. A like-for-like LED landing light that reuses the existing wiring and mounting with no change can qualify as preventive maintenance under FAR 43, Appendix A(c) — you install it and log it. You need an STC (or other approved data) when the installation changes the wiring or the structure, or when a bracket or adapter has to be added to make the new light fit.
Is a PMA part legal to install without an STC?
Yes, when it is an approved like-for-like replacement for the part already on the aircraft and nothing about the mounting or wiring changes. The PMA covers building the part; the like-for-like condition is what covers the installation. Change the mounting and you are back to needing approved data.
Are non-certified LED bulbs illegal?
The bulb itself is not the issue — the compliance is. Without a TSO or approved data behind it, you cannot demonstrate that the light meets FAA color and intensity requirements, and the liability for that falls on whoever installs and signs for it. Non-certified white-LED conversions that require swapping colored lenses for clear ones also void the original assembly’s approval for night flight.
Can I do the installation myself?
For true plug-and-play, like-for-like landing or taxi light swaps with no wiring change, yes — that is owner-performed preventive maintenance. Anything that removes a strobe power supply, changes wiring, or adds mounting hardware is A&P work, though under FAR 43.3(d) you may do the hands-on labor under a mechanic’s direct supervision while they make the logbook entry. Confirm the classification with your shop first.
Why is your kit several hundred dollars when I can find a light online for forty?
The online part is usually selling you a light. Our kit sells you an approved, installable upgrade for your specific airplane — STC engineering, aircraft-specific hardware, test data, and documentation your mechanic can sign behind. The gap is the certification work, not the markup.
Not sure where your install falls?
This is the whole reason we offer a free, one-on-one consultation. Tell us your aircraft make, model, and year and what you are trying to improve, and we will tell you exactly what fits, what is approved, and whether it is a preventive-maintenance swap you can log yourself or an STC install for your airplane. No obligation, no pressure — and a 15-minute conversation up front routinely saves owners hours of troubleshooting and rework later. Information is free.
Schedule your free lighting consultation →
Prefer to look first? Browse certified LED lighting or reach the team directly.
General educational guidance from Aero-Mach Wilco based on decades of hands-on experience. It is not a substitute for the judgment of your A&P mechanic or IA, who is responsible for classifying and signing off any given installation on your specific aircraft. Regulatory references (FAR Part 43, AC 20-41A, TSO-C30, TSO-C96) are provided for context; always confirm applicability with your maintenance provider.