Frequently Asked Questions about Amateur-Built Aircraft
DISCLAIMER: This is NOT an official FAA Page. The information
contained herein is provided solely as a reference guide to let you formulate
your own official questions to official sources. Always contact your
local FAA Office before relying on any information contained within an internet
If you find a dead link-please tell me. Write by clicking
FAA Order 8130-2d, titled "Airworthiness certification of aircraft and
related products" is found now on my Publications Page
AC 43.13-1b, Acceptable Methods, Techniques, Practices Aircraft Inspection
and Repair" To reach the AC 43.13-1b,
For forms used in applying for an airworthiness certificate, and a
repairman certificate. See my FORMS PAGE.
For copies of official guidance, Advisory Circulars and other FAA documents,
see my PUBLICATIONS PAGE.
For the last five years I have had the opportunity to inspect more than
one hundred Amateur-built aircraft and issue Experimental Airworthiness
Here are some common questions.
Homebuilding has grown tremendously in the last 20 years. More Home-built
Aircraft are now produced in the U.S. than factory-built aircraft. There
are many reasons, and all sorts of people are building their own flying machines.
Update- As of January 1,2001, more than have been certificated by the
FAA and are flying.
I have inspected all different kinds of homebuilts, from single place
ultralights through high performance planes.For more info about me, visit
my site at: the FAA PASS-MIDO Union home
. I am the National Representative for PASS-MIDO.
Again, this is NOT an official FAA Site.
Please contact your local FAA office for information in your area.
Q1. What Publications Does the FAA Put out to guide Me through the Process?
The FAA publishes a number of advisory circulars, which you can download
from my publications page
, or contact your local FAA office to get a copy.
, and AC 90-89A
the Amateur Flight test Handbook, are both documents you want to get
and study before proceeding with your project. They are available by clicking
on my publications page above.
2. How do I get an N-Number, and when should I do it?
N-Numbers are issued from the FAA Aircraft Registry in Oklahoma City,
Oklahoma. The phone number is:
(405) 954-3116. An FAA Manufacturing Inspection District Office or Flight
Standards District Office can usually provide you with the forms necessary
to begin the process. In any case, expect anywhere from 90 to 120 days to
complete the registration process. Many folks have walked in with a completed
airplane, less the N-Number, and had to wait while the registration is
You also do not want to register it too early for a number of reasons.
Some people give up on a project, and it may change hands several times
before completion. Having it built by one person and registered to another
can make it difficult to show who actually built the aircraft. Some states
also charge sales, use or personal property tax on airplanes, and get their
information from FAA registry files. It may be hard to convince your state
tax collector he shouldn't charge you for an airplane in your basement when
all you have is the first shipment of sheet metal on your floor.
3. My airplane is a well known kit. Do I have to have a 40-hour test
FAA guidance actually leaves the exact number of hours up to the inspector.
However, in general, if you are using a CERTIFICATED ENGINE - PROP combination,
the inspector may (or may not, its up to him/her) give you fewer test flight
hours. By certificated combination I mean if that EXACT model engine and
EXACT model prop has already been flying around on an FAA Type Certificated
airplane, say a Cessna 172, the inspector may give a 25- hour test flight
program. Hartzell and Sensenich both have lists of engines they have been
FAA certified with. FAA Order 8130.2C specifically gives guidenace to inspectors
in this area. The net affect is a certified engine alone in not sufficient
to reduce flight test hours, but rather the fact that a certified engine/propeller
combination has undergone previous FAA testing allows for credit to be given
in this area.
The fact that there are hundreds of similar kit airplanes of your model
has little bearing on number of flight test hours. If you follow the suggested
test flight program outlined in the FAA Advisory Circular 90-89A, it will
take you at least 40 hours to determine that your aircraft is "safely controllable
throughout its range of speeds and throughout all maneuvers to be executed",
which is what is necessary for you to certify to fly outside of your test
4. Hundred of similar kits are up and flying. Why do I have to test
fly in a limited area at all?
The FAA's predecessor, the CAA, made a determination back in the 1950's
after being petitioned by the EAA that as a United States Citizen, you have
the right to fly an aircraft YOU BUILT YOURSELF FOR YOUR OWN RECREATION AND
EDUCATION. However, in the interest of safety, if the aircraft did not meet
CAA/FAA certification requirements, YOU MUST FLY ONLY IN AREAS WHICH WILL
NOT ENDANGER OTHERS. Any aircraft, homebuilt or production, needs to be
tested for flight handling characteristics before it is let loose in the
airspace above others. Even if your kit is similar to others now flying,
the FAA has NOT made any determination that the design is safe, and your
own custom modifications may have affect flight worthiness of the craft.
5. My Aircraft is fast. You normally only give a 25-mile radius for
flight testing. Can I have 300 Miles? (Or can I have to the paint shop, avionics
The FAA usually recognizes a legitimate need for a larger area if in
fact you have a fast aircraft. Some homebuilts now travel at 250 miles per
hour or more. Talk over your needs with the certificating inspector BEFORE
he/she comes to inspect to see what you can work out. Typically they may
give you a 50-mile radius around a sparsely populated area for a fast airplane.
The paint shop, or avionics shop, however, IS NOT necessary for you to
conduct your flight test operations. It is best to either have the work
done before you begin to fly, or wait until after your test flights are
completed to do this type of work. You might be able to get a special flight
permit from a Flight Standards District Office Inspector to take the plane
to a shop work if it needs it . You have to ask for a "Maintenance Special
Flight Permit" or ferry permit. It is NOT automatic that such a permit will
be granted, but it might be.
6. What is the reference for the need for yearly "condition" inspection
on a plane with an experimental airworthiness certificate? The only reference
that I can find is FAR 91.409 para(c) which says that there is no inspection
requirement for an aircraft with an Experimental Airworthiness certificate.
Most everyone says that the condition inspection is a requirement but nobody
has been able to show me the rule requiring it.
Interesting you should notice, but yes, it is true, Experimental Airplanes
are exempt from the "Annual Inspection " requirements found in 91.409, of
a standard category aircraft. FAR 91.409 (c)(1) exempts experimentally certificated
aircraft from the normal inspection rules.
The legal authority and basis to require an annual "Condition Inspection"
is found in 14 CFR part 91.319(e), whereby the FAA Administrator (in this
case, the certificating inspector) may issue any "additional limitations
the Administrator considers necessary" to the aircraft's airworthiness certificate
(Operating limitations) when the aircraft receives a special airworthiness
certificate. FAA Order 8130-2C describes standard operating limitations
for all experimental aircraft, and, as a matter of routine, the requirement
for an annual "Condition Inspection" is found there.
7. Do you have any info or links to info on the different types of Experimental-exhibition
category airworthiness certificates and the typical limitations assigned
to them? A friend is considering a Yak52 and when I asked him about the operating
limitations he was surprised that there might be more than on a homebuilt.
Is there an A/C listing the "boilerplate" limitations? Does it vary greatly
from region to region? How about relocating in a different region?
You can see a typical set of Operating Limitations taken from FAA Order
8130.27 by clicking on the attached link.
8. I've been searching through the various FAQs and other Web info about
kit planes, but I have not been able to find anything about what is probably
the most important question facing someone who is thinking of building one:
do I have the skills necessary for the job? I am eyeing the Super Stallion,
but have no idea just what is involving in building something like that.
Do I have to have significant woodworking or metalworking experience?
A: Whether or not you have the skills to successfully complete a project
and move it from dream into reality is a question only you can answer. Many
people begin a kit or plans project, only to see it whither away in a basement
corner. Others, however, are successful in seeing a project through to completion,
and getting the rewarding experience of soaring in their own creation.
One way to see what it takes to make a successful outcome is to make contact
with other homebuilders, perhaps even help another with his/her project
so that you can see the skills necessary to make it fly. Contact the EAA
and ask about chapters in your area, or ask a kit or plans supplier for
names of builders of the plane you want to build nearby. Many times you
can find someone who has been through the process, and can give you an honest
assessment of what it takes. Be advised that, in my experience, many people
say it took them twice as long as the kit provider told them it should take,
cost a bit more than planned, and could take anywhere from a few months
to many years. I've seen kits built in several months, and kits that were
started in the 1960's and finished in the 1990's. When viewing pictures
of projects in various stages of construction, it is not uncommon to see
pictures of small children helping dad or mom in the early shots, and teenagers
in the final photos. One man showed me his pictures, and said "Here is my
first wife, helping with the tail. Here is my second wife, bucking rivets
on the wing. Here is my third wife, who helped work on the engine mount.".
While he had changed families three times, he remained focused on his project
without fail. He learned metal work, fuel systems, upholstery, electrical
wiring, the whole shot. If you have the desire, the skill is learnable. Note:
In my experience, those who work with their hands make the best craftsmen.
Machinists and mechanics usually take extreme pride in accuracy and do well.
I once inspected a homebuilt made by a doctor. Doctors and lawyers seem
to be "not the best" craftsmen. The doctor was a urologist. His aircraft
was inspected four times before it was ready to fly.
9. What are the rules for used experimental aircraft? If I buy a used
one that has been certified and has its N number can I still work on it
as though I built it or do I have to have an A&P work on it from then
A. The FAA regulates maintenance through FAR part 43. Far 43.1 states
that the rules of that part do (b) "...not apply to any aircraft for which
an experimental airworthiness certificate has been issued, unless a different
kind of airworthiness certificate had been previously issued".
In effect what this means is that any person may perform maintenance, preventive
maintenance, rebuilding, overhauling or alternations to an experimental aircraft,
unless that aircraft had previously held another type of airworthiness certificate,
i.e. standard, utility, acrobatic, transport, etc. If it is an amateur built
aircraft, then anyone can do the maintenance.
However, all experimental operating limitations contain additional limiting
factors. You will nearly always find a statement worded something like "This
aircraft cannot be flown unless it has received, within the preceding 12
calendar months, a condition inspection conducted in accordance with the
scope and detail of Appendix D of part 43, and the inspection is recorded
in the aircraft records." Further, the limitations usually also say "Only
the builder, when certificated as the repairman, mechanics holding an A
& P rating, and appropriately rated repair stations may conduct the condition
inspection required by the operating limitations". If the aircraft is turbine
powered, or surplus military, there may be additional limitations which
mandate a licensed mechanic perform the work.
The net effect, and to answer your question, is: 1. The operating limitations
will tell you who can do the work. 2. If amateur-built, you probably can
do the work, except for the annual "condition inspection". and 3. That condition
inspection will probably have to be done by an A & P, since there are
no "appropriately rated repair stations" for non-certified experimental
aircraft that I know of.
10. Does one have to have a current medical certificate to fly a privately
owned experimental aircraft, single seat, no passengers? Strictly for pleasure
flying? I have a Class III private license but I don't know if I can pass
a medical exam.
A. Yes, an experimental aircraft certificated under FAR 21.191(g) (amateur-built)
has, as one of its operating limitations, the requirement to hold a valid
category and class certificate. It is assumed that that includes medical
certification appropriate to the intended use, i.e. a minimum of a third
class medical. That requirement is found in the old FAR Part 61, item 61.3(c)
"Except free balloon pilots piloting balloons, and glider pilots piloting
gliders, No person may act as pilot in command or in any other capacity as
a required flight crew member of an aircraft under this part, unless he has
in his personal possession, an appropriate current medical certificate..."
This was reworded slightly in the recent FAR part 61 rewrite, but I don’t
have a copy just yet. The intent however, remained, although I can't give
you the exact wording. You may wish to investigate the option of a special
medical certificate. The standards for a third class certificate are found
in FAR part 67 are those required for an for a normal issuance certificate.
FAR part 67.19 outlines procedures whereby an applicant may apply for the
"Special Issuance" of a medical certificate for those persons who otherwise
do not meet the standard requirements. There may be special conditions, a
limited duration, or other special conditions imposed, but it may be possible
to obtain such a certificate. Without knowing your medical condition, it would
be hard for me to guess what would be possible. Talk to the AOPA, the EAA
or an FAA Designated Medical Examiner about your medically disqualifying condition,
and you might learn of others who are in similar medical shape who have been
successful in obtaining a special issuance certificate. By the way, Ultralight
aircraft, as defined in FAR part 103, have no such medical certification
requirement. However, some conditions which disqualify you from obtaining
a Class III medical certificate might also be hazardous in any flying condition,
so its best to talk to your doctor before making any decisions.
11. I have thought about powering my homebuilt with an APU Turbine Engine
conversion. Any problems you can think of right off the bat?
A. Yes, many. Check out a discussion of common problems with turbine
engine conversion gleamed from my favorite newsgroup, rec.aviation.homebuilt.
You can find it by click on this magic phrase: Should
I go Turbine Power?
12. What is involved, and is it possible, to get a homebuilt aircraft
certified as a standard single engine land classification and category?
A.Yes, theoretically it would be possible, provided you are able to
show compliance with FAR part 23 for the airplane, and FAR part 33 for the
engine, (and 35 for the prop). It is quite an extensive task to undergo
Type Certification. The current system of certification was developed in
the 1930's, when a producer "Certified" a design, and made multiple copies.
The builder had to show that the aircraft met the performance and design
rules of Aero bulletin 7, the predecessor to today’s FAR part 23. Over
the years, safety requirements increased as experience showed the need
for additional safety certification in design. The type certification process
has become much more extensive and expensive, however, and is not designed
to make it economical to certify a "one-off" airplane, but rather to certify
a prototype for a mass-production line, so that certification costs can
be spread over many units of production. This is one reason why so few aircraft
designs have been certified recently. The FAA has begun taking a new flexibility
towards applicant's efforts to find alternate ways to meet regulations. While
the standards in Far part 23 are there, there may be alternate means of complying
with regulations that are less expensive than others. For example, if a
regulation states the seats must withstand a certain g- force, you may be
able to show that the design of the airplane allows the fixed gear to take
some of that load. It really depends upon the aircraft involved. It can
be done, for a price on your part, but you'd have to decide if the price
is worth it. Review FAR part 23 and see if you think your airplane can be
certified to those standards.
13. My main concern is to get FAA approval to fly outside of the normal
experimental restrictions of day VFR only, i.e. IFR and night flights. In
lieu of going through Part 23 what would be involved in getting such authorization
under 91.319.c and d.2?
A. Usually the only requirement would be that the aircraft is properly
equipped for night and or instrument flight in accordance with FAR 91.205.
Under FAR 91.319(e), the "Administrator", i.e. the Certificating FAA Inspector
or DAR is allowed to proscribed any additional operating limitation he/she
finds necessary for safe aircraft operation.
When the inspector or DAR is inspecting your airplane for its initial
airworthiness certificate, he/she will look for the proper equipment as required
under FAR 91.205, and other FAR requirements. If you have the proper lighting,
strobes, electrical capacity, etc, he/she can approve Night VFR, and if you
have appropriate equipment for IFR operation as listed in the FARs, IFR can
be approved also. This is a common requested limitation, and is standard
fare for certification inspectors. However, most inspectors will advise you
that during the initial test flight, you should fly day VFR only. Afterward,
provided the aircraft has proper equipment, night and instrument flight is
14. This assumes I comply with the MEL for night and IFR flights. Is
there a formal procedure?
A. Be careful with the term MEL. MEL is usually referred to by FAA
as the minimum equipment list, specifically on a type of aircraft used by
a certificate holder (i.e. part 135 or part 121 air carrier.) The procedure
can be discussed with your local Manufacturing Inspection office or FSDO.
Contact them for exact answers in your area.
15. Also, I have seen references to the homebuilt having to be primarily
built by the owner/licensee. If I have the craft built professionally what
are the ramifications?
A. A professionally built aircraft was NOT built by
a builder for their own recreation and education, and therefore cannot be
certificated as amateur-built. See FAA Advisory circular AC 20-139, titled
"commercial assistance during construction of amateur-built aircraft, dated
4/3/96. It is available on my PUBLICATIONS PAGE
16. I got the bug to build a homebuilt aircraft, so I am in the process
of researching what is best for me. I am a aircraft mechanic for a major
airline and also have my private pilot cert. I am looking at the ultralights
and trying to get all the information I can before I start. I am leaning
toward a two place ultralight for cost reasons and less red tape. My question
is what is the difference in operating limits between a person flying a ultralight
that is over 254 lbs. without a private pilot certificate, and me with
a private pilot cert.? It seems to me there are a lot of people flying these
with no private pilot license.
A. I'm sorry to tell you that, in general, there are no such things
as two place ultralights. True Ultralights, requiring no airworthiness certificates
or pilot certificates, are limited under FAR part 103 to a single place
aircraft weighing less than 254 pounds. This is required by FAR part 103.
You can view all the rules of FAR part 103, and all regs by going to
the FAA AFS-600 information site.
The file is titled "far-103.txt".
Only three exemptions have been issued to waive the weight requirements,
and they have been issued for training purposes only. They are quite strict
in their purpose, and have been issued to three bodies, one of which is
The exemption allows a two place aircraft to be flown under ultralight
part 103 rules, only for the purpose of providing training to ultralight
pilots. The holders of these exemptions must perform their training to
the exemption requirements only, which include limits on weight, speed
If there are people flying aircraft weighing greater than 254 pounds, or
carrying more than 5 gallons of fuel, or not meeting any of the other specifications
of Part 103, and are not operating under the provisions of these three exemptions,
then they are flying an aircraft, not an ultralight, and are violating
FARs, and are subject to certificate revocation(if they hold a pilot's certificate),
fines, restraining orders, or other appropriate civil action.
Several publications have been written to guide people towards the FAA's
expectations on ultralight rules.
I have added the two Advisory Circulars the FAA has issued on Ultralights,
and AC 103-7.
They contain some out of date information as far as airspace goes, but
otherwise are still applicable today.
17. Are amateur-built aircraft safe?
A. As safe as staying in bed at home? Well, that depends. Some amateur-built
aircraft have excellent safety records. Others have less than perfect records.
All aircraft and forms of flight have some inherent risk associated with
them. Many builders and pilots fly because they don't want to live the same
boring life everyone else is doing. Its up to you to decide your risk tolerance.
You can get good information on safety from the
Experimental Aircraft Association.
They keep excellent safety records by aircraft model in a data base,
which is available upon request. Call the EAA's Information Services section
and ask for the accident data for any particular model. They keep data
going back to the 1970's, and can provide you with insight for helping you
choose a project.
18. What about amateur-built Helicopters?
A. Also a growing field. The Rotorway Exec and the Scorpion are two
designs that have been build in substantial numbers. A recent entry into
homebuilt helicopters is the
with hundreds of kits having been sold so far. NTSB accidents for this
aircraft are listed Here
. That is not to say it is necessarily an unsafe aircraft. All amateur-built
helicopters have had their share of problems. But this is a new helicopter
which is finding a wide public appeal, and has sold more kits than many
amateur-built airplane kit manufacturers. It's always best to do lots
of research on any kit company before shelling out large sums of money.
19. How do I know if I am dealing with an honest person when choosing
A. That's been the $64,000 question for many folks. Always research
heavily before investing. Some companies have excellent records and reputations.
Other struggle and go out of business before you get your aircraft completed.
Ask other builders of your model about their experience. Subscribe to newsgroups
like rec.aviation.homebuilt and feel free to ask. You never know without
doing your homework.
Building can be a rewarding experience, but it also can have unexpected
pitfalls. Choose your project carefully, and become a member of the
for help and advice.
20. What type of certification would apply to a cessna 180 that I would
install a turbine on without going for a stc, possibly experimental?
It depends on the reason for the "experimental". There is no such category
as simply "experimental". You have to have a reason. "Research and Development",
"Air Racing", "Exhibition" are three subcategories that might be valid.
If you do not wish to obtain an STC to fly it legally as a standard category
aircraft, then the information contained in FAA Order 8130.27 covers a
great deal of the information you need to know. This document has been
replaced by FAA Order 8130.2d, but the basic information from 8130.27 still
You can view a copy of 8130.27 at:
FAA Order 8130.27
I believe that the aircraft may fall into the requirements of a "Group
II" aircraft or "Group IV", based on the turbine conversion, and what your
local FSDO interpretation is. As always, talk to your local FAA Flight Standards
District Office (FSDO) before attemping any such modification. They are
the ones who have controlling interest in your area, and would be proscribing
any new operating limitations, so they are your best source of official
21. Do I have to keep a builders log when I build an aircraft, every
You should keep a builders log, though not necessarily for every day.
The reason you keep a builders log is to document that you, and not someone
else, did each step in the process. A good builders log will have entries
showing the beginning, and then entries at least at each major stage of the
contruction. For example, you may note the finishing of the tail section,
the elevator, the left wing, the right wing, the fuselage, the cockpit, etc.
Its a good idea to get a second set of eyes to look over your work at each
phase- and log the person who looked at it before close. The second set
of eyes just make it more likely that a missing washer, a loose bolt, etc,
will be caught before close. A good builders log will define who the builder
was for the inspector, a key item he/she is trying to verify in the course
of the inspection.
22.I am considering buying a prebuilt, but not flown or certified, Moni.
The original builder died before he finished all the paperwork. It has been
taxied but the widow is concerned about liability so she has not allowed
the partners to fly it. What would you recommend I look for in this design
if I decide to go look at it?
You have raised several troubling issues. Will it be eligible for an
amateur-built certificate? Only if the records exist to prove that the reason
it was built was for someone's own education and recreation. Before buying
such a project, it would be a good idea to talk to your local FAA office
who will be issuing the airworthiness certificate. Who is going to sign
the notarized statement that the aircraft was built for someone's own education
and recreation? You? The former partners? Talk to the FAA before getting
in too deep. Second issue you ask is the pluses or minus of a particular
design. The best source for this info is a model specific builders group,
or the EAA. Information Services at the EAA has great records of the history
of accidents or incidents for nearly all models. Check with them.
The other issue you raise, liability, is a growing question I receive.
I am not a lawyer, nor do I play one on T.V. Liability is something only
your lawyer can advise you on. Recently AVWEB
did an excellent piece on liability of home builders. I have provided
a reprint of the AVWEB article on liability
here. Please take the time to read it and understand that no written
waiver is going to compeltely protect you from the buyer's widow's claim.
On the other hand, to my knowledge, there has not yet been a successful
case litigated where a builder has been found liable for a crash. Chances
are eventually it will happen, but so far, some people have had to expend
large sums defending themselves in such cases, but no jury has yet awarded
claims that I know of.
23. Do Airworthiness Directives apply to Experimental Aircraft?
Yes!. In general, the FAA only issues Airworthiness Directives (AD's)
when an unsafe condition is found, and is likely to occur in other aircraft,
engines, propellers or appliances of the same type. For a more complete read
of the information, visit my Airworthiness Directives
page which explains the impact of AD's on Experimantal Aircraft and
why you have to comply.
24. I am ready to put a different prop on my homebuilt. Do I have to
do anything other than a logbook entry?
Yes. Look at your aircraft operating limitations. Usually (always) there
is a line in there that says something to the affect of "e This
aircraft may not be flown after incorporating a major change as defined by
14 CFR part 21.93, unless you notify the FAA, and their response is received
in writing. ". (Cover language) This language means if you make ANY changes
that could affect qualities of airworthiness of your aircraft, you must
contact the FAA. Usually it may mean a quick inspection by an FAA inspector,
or could require additional test flight hours. Rarely would the additional
hours be more than 5 or 10, but it is up to the FAA Inspector to decide
if you need to put it back into some kind of test flight program after a
I once certificated a land based airplane, and read the guy the limitations
as such. Later that year he put it on floats, and did not contact the FAA
before flying. Guess what. He crashed, and was cited for flying in violation
of his operating limitations. Turns out he forgot to do a new weight and
balance, and was outside his box. Such a change, just like changing anything
on a certified aircraft, must be done carefully, and reviewed by the FAA
prior to flying.
More information is posted here from time to time, so please check back
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