History of Limited Type Certificates

[Noha307]

The FAA has a list of all limited type certificates and their holders on page 8-2 of FAA Order 8130.2 It's a fascinating list to look at and I thought it would be interesting to try to figure out the story behind how each one was created. First the list:

A few of them are self evident. (e.g. Lockheed and the P-38). However, most of them are names I don't recognize. Others surprised me. (There's a LTC for the PB2Y? Why?)

• LTC-1 - B-17
• LTC-2 - B-25
• TCS L-3 - A-26
• TCS L-4 - A-24 (SBD)
• LTC-5 - PB2Y
• LTC-6 - LB-30
• LTC-7 - R-4
• LTC-8 - TBF/TBM
• TC L-9 - A-20
• LTC-10 - P-38/F-5
• LTC-11 - P-51
• LTC-12 - AT-10
• LTC-13 - B-34/PV
• LTC-14 - P-61
• LTC-15 - A-36
• LTC-16 - O-52
• LTC-17 - J2F
• LTC-18 - P-40
• LTC-19 - R-5
• LTC-20 - PBM
• LTC-21 - P-63
• LTC-22 - BC-1
• LTC-23 - F8F
• LTC-24 - OS2U/OS2N
• LTC-25 - FM
• LTC-26 - L-1
• LTC-27 - BT-9
• LTC-28 - PQ-14/TD2C
• LTC-29 - R-6/HOS
• LTC-30 - C-87
• LTC-31 - AT-9
• LTC-32 - BT-14
• AL-33 - B-26

One of the interesting things is that certain LTCs can be tied to specific airframes:

• TCS-3 - PVS's A-26, s/n 44-34774
• LTC-4 - S&W's A-24, s/n 42-54782
• LTC-6 - CAF's LB-30, s/n AM927
• TCL-9 - Howard Hughes's A-20, s/n 43-22197
• LTC-15 - WWE's A-36, s/n 42-83769
• LTC-33 - TGTC's B-26s, s/n 41-35071 and 41-35542

I'm amazed that so many individuals and organizations went through the effort to have an entire model of aircraft certified for only one or two airframes.

In other cases, it's strange that aircraft that were otherwise so similar received separate LTCs:

• LB-30 (LTC-6) and C-87 (LTC-30)
• P-51 (LTC-11) and A-36 (LTC-15)
• BT-9 (LTC-27) and BT-14 (LTC-32)

As to hints for some of the other owners:

• The "S and R Aviation Services" listed in LTC-1 is Aero Trader with the "S and R" standing for "Carl Scholl and Charles Ritzman".[1] The original holder of LTC-1 was Shell Aviation Corporation.
• A Paul V. Shields, a senior partner of the banking firm Shields & Company of New York and likely holder of TCS L-3, became chairman of Curtiss-Wright in April 1949 according to an article on page 22 of the 2 October 1951 issue of the Herald-News.
• LTC-15 was almost certainly held by a man described in an article on page 1 of the 21 November 1947 issue of the Charlotte Observer:
  

  STUNT PILOT TO TRY FOR NEW SPEED MARK
  WASHINGTON, Nov. 20. -(AP)- Woodrow W. Edmonson, a Lynchburg, Va., stunt pilot, landed here today and prepared to take off tomorrow in an attempt to break the Washington-to-Havana speed record. He arrived at 3:25 p. m. after a 39-minute flight from Lynchburg.
  His P-51 will carry a Virginia ham on the speed dash - a gift to the President of Cuba from the citizens of Lynchburg. He plans an eight-minute refueling stop at Jacksonville, Fla.
  

  
  Guess what was actually an A-36?
• The apparent owner of LTC-16, Holmberg Aerial Survey, was located in Chicago, Illinois according to an article on page 11 of the 13 May 1939 issue of the Bangor Daily News.
• Although I couldn't obtain access to the actual article, the "Hel-I-Cop Advertising Corporation" from LTC-19 is mentioned in an article titled "Wartime pilots turn flying know-how into new businesses" on page 3 of a 20 April 1947 issue of a Pasadena newspaper called the Independent.
• A news article from page 17 of the 21 September 1946 issue of the [Montreal] Gazette seems to have the answer for the origin of LTC-20:
  

  Speaking of Flying Sportsmen
  Capt. Carl F. Krogmann, president and general manager of Potomac Airlines, Inc., who piloted a large party of sportsmen and women from Washington D.C., for the Labor Day weekend angling on New Brunswick's famous Miramichi waters, plans to bring into the province at least two, if not more, hunting airloads in November.
  The "package air tour" experiment by Krogmann was a success. All were back home in time to be at their respective jobs Tuesday morning and 14 got real thrills as good-sized Atlantic silver salmon were hooked at "Bill" Craig's camps. The largest salmon landed was a 16-pounder. Fourteen of the party spent Saturday, Sunday and part of Monday in camp.
  

• Richard R. Carlisle, who is likely the holder of LTC-25, was a chief test pilot at Pearl Harbor and became commander of a naval air reserve base in Birmingham, Alabama in 1947. Interestingly, at the new base's commissioning a "Navy plane" was christened "Miss Alabama of 1947" as part of the ceremonies according to an article on page 6 of the 15 November 1947 issue of the Birmingham News. Could this have been an FM-1?
• According to an article on page 16 of the 25 March 1947 issue of the Akron Beacon Journal, Executive Airlines, Inc. the holder of LTC-26, owned by William B. "Bill" O'Neil had been operating "[t]win-engined Cessnas" out of "Cleveland airport".
• Judging by the multiple classified ads in the January and February 1947 issues of the Fort-Worth Star Telegram, that describe "N. A. Kalt" of the "NAA Plant", the apparent holder of LTC-28, he was a surplus dealer. A few, including one on page 9 of the 1 February 1947 issue, mention a "Harlow", GB-2, and "D-17S" for sale by him.
• An old aircraft listing reveals the full name of the holder of LTC-31 was Louis S. Rehr. The current paperwork states the holder lives in Coral Gables, Florida. A Lieutenant (later Major) Louis S. Rehr, who lived in southeast Florida, was B-26 instructor and combat pilot. Maybe he trained on AT-9s and liked them so much he ended up acquiring the type certificate?
• A North American test pilot, Paul J. Franklin, had his plane unsuccessfully stolen according to page 3, part 2 of the 13 October 1948 issue of the Los Angeles Times. This name matches the one on LTC-32. (For those wondering, based on a picture, the stolen plane was not a BT-14.)

Some final observations:

• I have to wonder if a few of them were ever even were used. Did any civilian - in the United States, at least - ever fly a PB2Y, AT-9, or OS2U?
• The first LTC was approved no later than 2 December 1946 and the last no earlier than 14 July 1959. However, the vast majority were first approved in the 1946-48 time span.

Last edited by Noha307 on Mon May 03, 2021 10:19 am, edited 2 times in total.

[Dave Hadfield]

Wow, that's a heck of a lot of homework. Nice job!

It's useful to understand that not all the categories translate to regulatory approval in other countries.

We have no Experimental category, for example.

And the USA does not recognize our Owner Maintenance category.

And for me to take the new Hurricane XII to OSH, I will have to apply for an approval with the FAA even though it has an Approved flight authority here.

Dave

Last edited by Dave Hadfield on Mon May 03, 2021 8:34 am, edited 1 time in total.

[Chris Brame]

I'm surprised I don't see an LTC listed for the B-18 or B-23 - were there any?

[Noha307]

Wow, that's a heck of a lot of homework. Nice job!

Thanks!

It's useful to understand that not all the categories translate to regulatory approval in other countries.

We have no Experimental category, for example.

And the USA does not recognize our Owner Maintenance category.

And for me to take the new Hurricane XII to OSH, I will have to apply for an approval with the FAA even though it has an Approved flight authority here.

Interesting. I'm not familiar with the categories in Canada. What are they?

One of the curious aspects of limited category that made me want to learn more about it was that the description of it in the Code of Federal Regulations is very short and vague when compared with the other categories. The definition is basically a self-referential statement that amounts to "a limited category aircraft is any aircraft with a limited type certificate" with no further explanation. I did a quick word count (not including the section headings) on the definitions of various non-standard categories according to Part 21 of Title 14 of the Code of Federal Regulations (aka the FAR in "FAR/AIM") and here's how they break out:

• Primary Category: 418 words
• Restricted Category: 414 words
• Light Sport Category: 440 words
• Experimental Category: 896 words
• Limited Category: 89 words

Also, with the exception of the limited category, all of the above were last amended by 1992 or later. The limited category, however, was last amended in 1965.

The other thing I didn't realize before looking into it was that limited and restricted are two different categories. I think I had always just assumed that they were two different terms for the same thing since the words have a similar meaning. Ironically, the CFR entry for the restricted category mentions "surplus aircraft of the Armed Forces", but the entry for limited does not. In regards to the latter the phrase "surplus military aircraft" only appears in FAA Order 8130.2.

If you read through some of the LTCs in the list above (also, I think someone pointed this out to me before), the common thread appears to be that they all allow use of military manuals. So, the defining characteristic of limited category aircraft seems to be the exception that they don't have to conform to FAA standards.

I just took a look at the FAA's history of n-numbers and I noticed that the requirement to include a "C", "L", "R", or "X" was dropped at the end of 1948 - which is right about when the last of the restricted category aircraft were original certified. So I wonder if there might be some connection between the two. The other interesting thing it notes is that, although not stating exactly when, the "R" for restricted was added "later" than the other letters. While I could already pretty well guess that the limited category did not exist until after the war, it does point out that the restricted category predated it. This means that, for some reason, the CAA (the FAA did not exist until 1958) decided that the aircraft that would eventually be registered as limited should be separate from the restricted category.

One other consideration that might explain the emergence of the restricted category is the expected boom in postwar air travel that never materialized.

I'm surprised I don't see an LTC listed for the B-18 or B-23 - were there any?

Interesting point. I didn't see the B-18 or B-23 mentioned either, so I have to assume not. You would think there would have been given their use as executive aircraft after the war, but I guess no one ever bothered with it.

There really aren't that many. I myself was surprised when I found out that the a list of limited category aircraft could fit entirely on one page. It's really a strange category because: a) all but one or two of the aircraft were registered in a three year time span, and b) the parameters for inclusion are not really all that well defined.

It really seems to be a product of a very specific time period in American history. If I had to venture a guess, this might partially explain the current situation with Warbird Adventures and the FAA. It's an old regulation that is paradoxically very specific, but also very poorly defined. Not to get off track with current issues, but if you look at the arguments in the case, one of the central issues is that the operators had one understanding of the law (specifically in regards to what constitutes compensation) and the FAA had another.

I have to wonder: Could any aircraft receive a limited category type certificate today? What if I wanted to register, say, an F-16? Would it be allowed? Or would it go under some other category like restricted?

[bdk]

I have to wonder: Could any aircraft receive a limited category type certificate today? What if I wanted to register, say, an F-16? Would it be allowed? Or would it go under some other category like restricted?

My understanding, though I write with no particular authority (just an opportunity for people that really know to shoot arrows at me):

I don't think you can add to either the Limited or Restricted categories. That time has passed and certification is much more difficult these days.

Also, to fly an aircraft in the Limited or Restricted category I think you needed a Letter of Authorization, now a Type Rating. You also need the latter for gross weights over 12,500# and 850(?) HP or greater for experimental aircraft.

I think an F-16 would fit into the Experimental-Exhibition category.

[bdk]

I'm surprised I don't see an LTC listed for the B-18 or B-23 - were there any?

Interesting point. I didn't see the B-18 or B-23 mentioned either, so I have to assume not. You would think there would have been given their use as executive aircraft after the war, but I guess no one ever bothered with it.

Not in the Limited Category, they have standard Type Certificate Data Sheets held by the Douglas Aircraft Company:

Model: TCDS No. TC 2-577, Rev. No. 0, Douglas Aircraft Co., Inc., Army B-18A
Model: TCDS No. TC 2-576, Rev. No. 0, Douglas Aircraft Co., Inc., B-23

[JohnB]

Peter M. Bowers in his Boeing book shows a TWA B-17 used for route proving and various tasks in the mideast.
I believe it was later given to the Shah of Iran.
Correct me if I'm wrong, but doesn't a Limited TC allow companies to transport their own employees in a non-ATC aircraft?

I would wager that Grumman getting approval for a Bearcat has to do with Al Williams flying one post-war as the final Gulfhawk.

The H-5 is simple enough, it's a military surplus machine and not a commercial S-51 which received helicopter type certificate number 2, after the Bell 47.

Likewise the R-6; it does not have a civil counterpart, unlike most other Sikorskys. I have never seen a photo of a civilian R-6, but in this hobby you never say never.

[Mike]

It’s worth noting that the P-51 Limited TC only covers the C, D and K, which is why most of the new-build high-back Merlin Mustangs are registered as P-51Cs (Bs have to be registered as Experimental)

[Noha307]

Found a few more likely origins of LTCs:

• LTC-12 was held by a man named Leland H. Cameron. Mr. Cameron apparently had a business in southern California called Allied Aircraft/Advanced Industries/Aerospace Products that converted warbirds to executive aircraft. He may also may have a connection to another LTC, LTC-33, as his company was apparently responsible for converting one of Tennessee Gas Transmission's two B-26s, s/n 41-35071. He also owned an AT-11, which I find interesting because it is not too far off from an AT-10 in terms of configuration. One other interesting note about LTC-12, for some reason the two letter manufacturer codes for the AT-10 were all listed as if they were different variants. (e.g. "AT-10, AT-10BH, AT-10GL, AT-10GF")
• An obituary on page B-4 of the 1 July 1970 issue of the [Long Beach] Independent notes that Robert Brooke Utterback, the likely holder of LTC-17, was the owner-operator of an aircraft and aerospace company bearing his name. He was also both a Royal Canadian Air Force and United States Army Air Force pilot during World War II. Interestingly, he is noted as being an "official of the...Historical Committee San Diego Hall of the Aerospace Sciences" - which I assume to be related to the San Diego Air & Space Museum. At one point, the SDASM owned a J2F, BuNo 33594. While the ownership history does not exactly match up, it's possible that this aircraft came from Mr. Utterback.
• The former holder of LTC-18, Boardman C. Reed, was a World War II B-17 and Korean War F-51 pilot. He wrote a memoir titled Flights Forgotten...and Remembered and one webpage notes he flew the Planes of Fame's P-51. The LTC was acquired by Christopher Prevost in 2004. I presume this was to allow him to convert his P-40N, s/n 42-105306, to a two seat model.
• The "Mustang Aviation" mentioned in LTC-22 was apparently a flying school and, based on an article on page 6 of the 23 February 1943 issue of the Paris News, was "invited to contract for training non-combatant elementary and advanced students who are in the Air Forces enlisted reserve". While it is unclear if they accepted, if they did it would make sense that they would have ended up with a bunch of BC-1s that they wanted to use after the war.
• The "Stolp-Adams Company" mentioned in LTC-29 is apparently the same one that would go on to design the Stolp Starduster biplane. Page 143 of the June 1949 issue of Popular Mechanics includes a feature on the company's repair station in Compton, California. As an aside, similar to LTC-12, the actual paperwork includes an error, listing an "R-5A" instead of an R-6A.
• The origin of LTC-30 was apparently an abortive expedition to China by the Reynolds Boston Museum in April 1948. The airplane RY-1, BuNo 67798, was flown by the LTC holder, William P. Odom. Two other interesting notes about Mr. Odom he flew the record setting Beechcraft Bonanza Waikiki Beech that's now in the National Air and Space Museum and was killed in the crash of a P-51C in 1949.

My understanding, though I write with no particular authority (just an opportunity for people that really know to shoot arrows at me):

No worries, I'm in the same boat.

I don't think you can add to either the Limited or Restricted categories.

According to an article from Vertical magazine, the H-47 and H-60 were recently registered in the restricted category. The first revision for the H-60 RTC is from 2016, which means it was not just an updated version of an earlier RTC.

Peter M. Bowers in his Boeing book shows a TWA B-17 used for route proving and various tasks in the mideast.
I believe it was later given to the Shah of Iran.

Interesting! Looks like you're right. A B-17G, s/n 44-85728, was indeed operated by TWA and later given to the Shah.

Correct me if I'm wrong, but doesn't a Limited TC allow companies to transport their own employees in a non-ATC aircraft?

This note about the above aircraft certainly hints at that:

Trans World Airlines had the B[-]17G 44-85728 converted to executive use for development of new route structures on TWA’s foreign runs. Boeing was hired to rebuild the Fortress at their Seattle facility, which the company saw as a opportunity to explore the post-war market for similar Fortress conversions. Boeing Model 299AB came out and obtained the registration of NX4600 for the aircraft after it was purchased in June 1946. Once the modifications were completed, TWA deployed NX4600 to the Middle East and used it to transport TWA executives.

(Source: The Dakota Hunter)

I would wager that Grumman getting approval for a Bearcat has to do with Al Williams flying one post-war as the final Gulfhawk.

I think you're probably right.

EDIT: Added information about LTC-17.

EDIT (23-06-04): A better quality version of the picture of s/n 44-85728 is available on Wikimedia Commons.

Last edited by Noha307 on Sun Jun 04, 2023 6:32 pm, edited 1 time in total.

[bdk]

I don't think you can add to either the Limited or Restricted categories.

According to an article from Vertical magazine, the H-47 and H-60 were recently registered in the restricted category. The first revision for the H-60 RTC is from 2016, which means it was not just an updated version of an earlier RTC.

You are probably right. I think Restricted category is often used for things like agricultural purposes.

[JohnB]

Up here in my neighborhood, I have seen commercial firefighting H-60s and (rather more surpringly) H-47s.
I assumed they had Restricted certificates.
The H-47 was wearing a nice paint job with large "Billings" titles.

[Noha307]

I have to wonder: Could any aircraft receive a limited category type certificate today? What if I wanted to register, say, an F-16? Would it be allowed? Or would it go under some other category like restricted?

I just answered my own question. According to a note on LTC-31:

No original NL airworthiness certificates may be issued after 8/31/48.

Interestingly, a note on the third and current revision for that same LTC states:

On August 24, 2015 a search of all FAA files and records was conducted and no type design records were found.

This makes me wonder if any were ever submitted in the first place. To me, the whole vibe of these LTCs is that they were done quickly and with minor oversight. I wonder if the ease of the process meant that a few people, who would have otherwise not submitted an application, did so because it took such little effort. This might explain why there are a bunch of LTCs for aircraft we've never seen fly in civilian hands - the people that registered them were generally not that serious about it in the first place and therefore never followed up on it. As evidence of this, I present this newspaper article from page 10 of the 2 October 1948 issue of the St. Louis Star-Times I just came across that demonstrates the attitude of the CAA at the time. Note that it is dated only two months after LTCs were closed to further submission:

CAA To Provide Faster Certification Of Aircraft And Parts

WASHINGTON, Oct. 2 - Faster certification of aircraft and aircraft parts will be ac[c]omplished hereafter by issuing type certificates in the nine regions of the Civil Aeronautics Administration instead of at Washington, D. W. Rentzel, administrator of civil aeronautics, has announced.
"The change is more one of paper than of policy," Rentzel said. "Our aviation safety agents in the field have been doing all the technical work of testing, leaving to the Washington office the sole task of establishing policy, reviewing, and in very rare cases, resolving differences of opinion."
To certificate a new plane, the CAA establishes a Type Certification Board in the office of the region where the plane is manufactured, consisting of technical experts on various aspects of design, operation and maintenance. This board works with the manufacturer throughout the whole process of design and production of the first plane, and then rides the plane through 150 hours of accelerated flight testing. Upon its decision as to the safety of the plane, and its meeting of the pertinent civil air regulations, the manufacturer is given a type certificate, and later a production certificate allowing him to duplicate the design.
Heretofore, this board has given an airworthiness certificate to planes pending final issuances of the type certificate, and allowed the plane to operate under a[ ]"tentative approval." Hereafter the type certificate will be issued immediately upon decision of the board in the CAA region.

[Noha307]

While working on the Warbird Modification Companies thread, I decided to look into Air Trading Corporation - the holder of both LTC-8 and LTC-13 - a bit more. As it turns out, I got lucky. The front page of the 27 July 1946 issue of the Daily Home News has an article describing the company and its employees:

Converting Five Navy Bombers Into Cargo Carrying Planes

North Brunswick Airport Officials Plan to Extend Operations to Foreign Markets

Work on modifying five TBM Grumann [sic] Avengers to be used to carry cargo is being carried on at North Brunswick Airport by the Air Trading Corporation of New York City.

The former Navy bombers are among nine acquired by the corporation since it was formed by veterans December 13, 1945. The other four are in service.

Two local men are interested in the outfit, which plans eventually to extend its operations to foreign markets. The local veterans are contributing their experience in the flying field until they complete their studies and devote full time to the work as a career.

John Hall Wiles of 5 Mine street, who serves as an ensign in the Navy, piloting several types of aircraft during a year and a half of service on this continent, heads the research department. Wiles is attending Rutgers University and expects to receive his degree in a few months. Until that time, he and Chester Holman of 233 Howard street will receive no compensation from the outfit. Holman is serving in the mechanical division and is a student pilot at North Brunswick.

Wiles Attended Rutgers

Wiles, a graduate of New Brunswick High School, attended Rutgers before the war. He obtained his commercial license at Hadley Airport under a CPT program after training by Unger Aircraft.

The pilot served with Pan American Africa Limited for a year before the invasion of African in [sic] November 7, 1942. He returned to the state just before Christmas and became a test pilot for Bell Aircraft in Buffalo, N. Y., for a year. He then spent a year with Eastern Aircraft testing ships at Linden and Trenton before entering the Navy.

Since his discharge last December, Wiles spent a great deal of time on an experiment and has developed a rotary-wing type of aircraft, similar in appearance to the Rohrback design, but operating on an entirely different principal [sic]. Future research work on the development is now being carried on by Aeroflex Laboratories, in Long Island.

Wiles became interested in the type of corporation with which he is now affiliated shortly after he left the service. Holman has also been interested in aviation for several years and has successfully built several gasoline model planes, winning contests in the area. He served with the Navy during the war.

Partners Listed

Richard Seitzman of New York City, who was a captain in the Army Transport Command, is president of the corporation. George Arents of New York City is chief pilot. Arents was a commander in the Navy Ferry Command serving in the Pacific. The other pilot is Neil Seitzman of New York, treasurer of the corporation, who served in the ETO as a captain in the Army Air Force. The Avengers, when converted, will carry three tons of cargo. One ton may be carried in the bomb bay of the huge single engine ship. Work on one of the ships is nearing completion.

The corporation is ready to offer its facilities for non-scheduled charter hauling and, if the demand is great enough here, will fly a few ships out of North Brunswick.

Unfortunately, only two months earlier the corporation had lost an Avenger in a landing accident that killed the two men onboard. Interestingly, one of them was a Civil Aeronautics Board instructor, who, I have to speculate, may have been riding along for certification purposes.[1][2] This was not the company's first landing accident, as earlier that same month another TBM had been damaged in a nose over at the same airport by a different pilot.[3] One year later, in May 1947, the widow of the CAB inspector sued the company for negligence.[4] This lawsuit may have doomed the company, as in June of of that year a B-18 belonging to the Air Trading Corporation was noted as being sold at a sheriff's sale in Oklahoma City.[5]

As a final note, unsurprisingly, test pilots being holders of LTCs seems to be a minor theme, as the holders of LTC-25 and LTC-32 were also of that profession.

[Chris Brame]

This lawsuit may have doomed the company, as in June of of that year a B-18 belonging to the Air Trading Corporation was noted as being sold at a sheriff's sale in Oklahoma City.

Hmm. Wonder which one it was? Checked Geoff Goodall's list and the only one listed with Oklahoma connections was 39-25/N62477, but Air Trading and Norman Blake (the buyer) don't show up in that history.

[Randy Haskin]

It’s worth noting that the P-51 Limited TC only covers the C, D and K, which is why most of the new-build high-back Merlin Mustangs are registered as P-51Cs (Bs have to be registered as Experimental)

Same reason the Cavaliers built for the civilian market recycled NAA/USAAF identities and the ones built for military contracts used new 67,68, and 72 serials.

And why the 67/68/72 aircraft that now fly on the US register use "heritage" NAA/USAAF identities that likely have nothing to do with where the metal came from.