EricJ Posted July 21, 2019 Report Share Posted July 21, 2019 (edited) 52 minutes ago, PT20J said: Well, as you pointed out, TSO-C30c is for position lights. I don't believe there is a TSO for landing/taxi lights. Without at TSO, you need traceability to an industry standard (such as the incandescents) or an STC (such as Whelen). Obviously there are plenty of learned opinions in this area that differ, some even expressed by FAA reps. What "industry standard" should be applied? Often "standards" aren't, or just cover external dimensions and maybe electrical connectivity for interchangeability, or a part may meet multiple standards, etc., etc.. If a specific standard isn't cited, it's hard to claim one applies, or which one applies and which one doesn't. MS25241-4522 covers 4522 lamps, but if it isn't cited it's hard to say it applies, and it probably wouldn't be cited if it contained a bunch of specs that weren't relevant to the application. If there's no TSO for minimum specs, it's hard to claim you don't meet them. Changing a landing light also doesn't seem to meet the criteria for a major mod or alteration. There does not seem to be a shortage of people willing to say how it actually is, but they're not consistent. Hence the usual discussions on the topic. Edit: the relevant FAR for landing lights isn't very stringent: § 23.1383 Taxi and landing lights. Each taxi and landing light must be designed and installed so that: (a) No dangerous glare is visible to the pilots. (b) The pilot is not seriously affected by halation. (c) It provides enough light for night operations. (d) It does not cause a fire hazard in any configuration. OTOH, the requirements for position lights are pretty detailed to cover things like angular coverage, chromaticity of the light, etc., etc. Hence TSOs for those. Edited July 21, 2019 by EricJ Quote Link to comment Share on other sites More sharing options...
jetdriven Posted July 21, 2019 Report Share Posted July 21, 2019 (edited) On 10/16/2018 at 5:10 AM, Hank said: Before sending off to the FAA to approve an LED landing light, is your existing incandescent light "approved"? TSO, PMA, anything? The GE bulb I used (and all previous owners of my plane since it left the factory in 1970) is not, and has no paperwork other than whatever Aircraft Spruce supplies with it, at an affordable aviation price of only four times Home Depot . . . . It is best to know the answer to your question before opening a can of Federal Worms, and avoid Form 337s for things that the FARs do not call Major Modifications. After all, what is the title of Form 337? It isn't for minor modifications, and shouldn't be used to cover your A&P and IA's backsides. Exactly. If it’s minor, don’t fill out the 337, thus declaring it Major, to “cover your backside”. Edited July 21, 2019 by jetdriven Quote Link to comment Share on other sites More sharing options...
Hank Posted July 21, 2019 Report Share Posted July 21, 2019 9 hours ago, PT20J said: Every thread about LED landing/taxi lights seems to devolve into a discussion about what is "legal" to install in type-certificated aircraft. Here's a way to think about it: When the airplane left the factory, it was issued an airworthiness certificate. Every component in it was "legal." Now, a year later, if something breaks and you buy a replacement part from Mooney, it can be installed with a logbook entry and it's still legal. Suppose you leave your recognition lights on and melt a wingtip lens. You decide to buy a lens from LASAR rather than Mooney. The LASAR lens is manufactured under a PMA. This means that it has been approved as an acceptable replacement for the Mooney part and so it can be installed with only a logbook entry. Want to replace the Mooney sunvisors with Rosens? Well the Rosen visors are a different design than the originals so a PMA wouldn't apply. But, Rosen has an STC so they can be installed with a 337 and a logbook entry. Suppose you want to install an ADS-B out transponder. The transponder will be TSO'd which means that it meets a specification approved by the FAA for use in aircraft and so it can be installed with a 337 and a logbook entry. OK, so far? The FAA allows certain parts that meet established industry standards to be used on type certificated aircraft without a PMA or STC or TSO. Commonly cited examples are nuts and bolts and safety wire. Incandescent landing lights fall into this category. A 4522 lamp is made by several manufacturers to an industry standard, and they are interchangeable. Replacing one with another requires a simple logbook entry. There is no such industry standard for the LED replacements. This is why Whelen has an STC for the Prometheus lights. To be "legal", replacement of the incandescent lights specified by Mooney with an "equivalent" LED requires an STC'd part and a 337 and a logbook entry. You may or may not think this is reasonable. Your IA may or may not care. But that's the way it works. Skip Way too many 337s there, Skip. Here is the list of Major Airframe Alterations from FAR 43 Appendix A: FAR 43 - Appendix A Major Alterations, Major Repairs, and Preventive Maintenance (a) Major alterations (1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations: (i) Wings. (ii) Tail surfaces. (iii) Fuselage. (iv) Engine mounts. (v) Control system. (vi) Landing gear. (vii) Hull or floats. (viii) Elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights. (ix) Hydraulic and electrical actuating system of components. (x) Rotor blades. (xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft. (xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems. (xiii) Changes to the wing or to fixed or movable control surfaces which affect flutter and vibration characteristics. Also included in this Appendix are Major Alterations to the Engjne (not applicable to landing lights) and Propellor (not applicable to landing lights), as well as Major Repairs (not applicable to replacing landing lights). So which losted item, selected from the FAA's list of i-xiii do you think changing the landing light falls under? That's right, none of them! Take out incandescent, put in LED, get your A&P to sign your logbook. Done! It's NOT a Major Alteration, so no Form 337 needs to be filed. 1 Quote Link to comment Share on other sites More sharing options...
EricJ Posted July 21, 2019 Report Share Posted July 21, 2019 (edited) 1 hour ago, Hank said: So which losted item, selected from the FAA's list of i-xiii do you think changing the landing light falls under? That's right, none of them! Take out incandescent, put in LED, get your A&P to sign your logbook. Done! It's NOT a Major Alteration, so no Form 337 needs to be filed. Even better, you don't even need your A&P or IA to sign it! Replacing position or landing lights falls under Preventive Maintenance under Part 43 Appendix A, c-17. This is work an owner can do, but a logbook entry should be made. The only wiring an owner is allowed to repair is the landing light circuit, per Part 43 App A c-16. The above, plus the FAR 23.1383 landing light requirements quoted above, tell you that the FAA is generally not overly concerned with details around landing lights. The requirements are basic, owners are specifically allowed to replace them (and position lights, and any related reflectors and lenses), and the only wiring repairs that fall under Preventive Maintenance (i.e., that an owner can do) is to the landing light circuit. Nevertheless, your IA that signs your logbook will have an opinion, and if you want them to sign your annual, their opinion is the one that matters. My IA is one of the grumpy experienced guys that doesn't tolerate owner maintenance and is a stickler for crossing t's and dotting i's on part traceability. But if it falls under Preventive Maintenance in 43 App A, I'm good, and I've replaced my landing light and position lights with LEDs (not even expensive ones!), changed my own battery, did some fiberglass repairs to my cowl, etc., etc. As long as *I* put it in the logbook and sign it, as required, I'm good per the regs and he signs my annual. Edited July 21, 2019 by EricJ 1 Quote Link to comment Share on other sites More sharing options...
PT20J Posted July 21, 2019 Report Share Posted July 21, 2019 (edited) Let's take the sunvisor example since that might be even more ridiculous than a landing light (but it's the same rationale) Rosen designed a new, improved sunvisor. Only "approved" parts can go on a type certificated airplane, so how does Rosen make it legal to install it? The part wasn't made by Mooney (holder of the type and production certificates). It doesn't conform to Mooney specs, so a PMA authorization doesn't apply. It's not an owner produced part. There is no applicable TSO. It's not a standard part like a nut or bolt. So, it gets installed under an STC. That's the authorization that allows it to be installed. And the FAA considers STCs to be major alterations by definition and requires a 337. I installed Rosen visors on my previous and current Mooneys. I did not file a 337 for the first plane and doubt that anyone has noticed in the 20 years since I sold it. On the current plane, I decided to keep it "by the book" and paid an IA $100 to inspect my installation and file the 337. It's up to everyone to decide how "by the book" they want to be (I've obviously been inconsistent). Still, I think it's good to understand the FAAs rules and policies. That's my only point. Skip Edited July 21, 2019 by PT20J 1 Quote Link to comment Share on other sites More sharing options...
Raptor05121 Posted July 22, 2019 Report Share Posted July 22, 2019 Well put, Skip. Quote Link to comment Share on other sites More sharing options...
NotarPilot Posted February 5, 2020 Author Report Share Posted February 5, 2020 Anyone install the Parmetheus Pro in their plane yet? I’m not sure if it got brighter or they refocused the beam but Spruce’s website has it as 175,000 candela now. Quote Link to comment Share on other sites More sharing options...
PJClark Posted February 9, 2020 Report Share Posted February 9, 2020 One of my two cowl mounted landing/taxi lites is out...so I'm doing this with Sunsetter G2s using the more liberal of the approaches above. Can anyone share some instructions on how to do this R2 operation on an 86 M20K? The Mx manual I downloaded is vintage 1997 and shows nothing about the cowl mounted lights Quote Link to comment Share on other sites More sharing options...
OSUAV8TER Posted February 9, 2020 Report Share Posted February 9, 2020 I carry both the Whelen Parmetheus Pro PAR 36 and PAR 46 sized bulbs. They are the best lights out there for the dollar before going to HID. Here’s the PAR-46. Around 170k candle power. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
OSUAV8TER Posted February 9, 2020 Report Share Posted February 9, 2020 Here’s the PAR-36Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
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