Forum: aviation.stackexchange.com
Tags: <aviation-history><airspeed><fixed-wing>
Title: What is the slowest fixed-wing airplane?
Question: It's easy to find information about the fastest airplanes, in different categories (e.g.  X-15 ,  SR-71 , the  Concorde  etc), but what is the slowest one? Which powered, manned airplane is capable of sustained level flight at lowest velocity?

Answers:
sents: text: The Gossamer Albatross is a human-powered plane with a top speed of 29 km/h (18mph).
text: It was used to cross the English Channel and seems to meet the criteria of the question.
answer_details: author: aviation.stackexchange.com/users/22749/Michael Schumacher
score: 90
sents: text: The Antonov AN-2 has no stall speed quoted in the operating manual and can fly under full control at about 30 mph.
text: Thus if the headwind is sufficiently large the aircraft will move backwards with respect to the ground.
answer_details: author: aviation.stackexchange.com/users/15202/Brilsmurfffje
score: 61
sents: text: The Harrier , Yak-38 , Yak-141 , XV-15 , and V-22 are all fixed wing aircraft.
text: All can hover in mid air, controlled.
text: So they are in controlled flight at 0 velocity.
text: At least the Harrier can even be in controlled flight flying backwards, so with negative velocity.
text: The others may as well, I don't know.
answer_details: author: aviation.stackexchange.com/users/900/jwenting
score: 45
sents: text: now, if you're looking at modern, more commonly used transportation, powered paragliding would probably take the cake.
text: CC BY 3.0, https://en.wikipedia.org/w/index.php?curid=13110495
text: Powered paragliders usually fly between 15 and 50 mph (25 and 72 km/h) at altitudes from 'foot-dragging on the water' up to 24,000+ ft (5400 m) https://en.wikipedia.org/wiki/Powered_paragliding
text: The beginners equipment are often the slowest, and with proper skill, and the right weather, can have a stall speed of zero .
text: Whilst being lifted by a thermal, the only thing that will push the glider forward is the natural tilt.
text: naturally, on a still day, the slowest of equipment will stall at below 10mph .
text: Disclaimer: this is not an airplane, but it is a fixed wing vehicle, made to primarily move forward to generate lift, akin to most airplanes.
answer_details: author: aviation.stackexchange.com/users/11387/tuskiomi
score: 21
sents: text: If you are including historical aircraft, the Wright Flyer averaged 10 fps (approx 6.8 mph or 11 kph) over
text: it's first 120 foot flight in 1903.
text: Reference: https://airandspace.si.edu/exhibitions/wright-brothers/online/fly/1903/triumph.cfm
answer_details: author: aviation.stackexchange.com/users/22751/user112358
score: 18
sents: text: Building it just for very slow speed does not look practical (if you really need this, use helicopter).
text: Some old planes may be slower, but they do not use the newest technologies and may not be built for slow flight anyway.
text: Some patrol, agricultural planes may benefit from slow flying, but we need something more extreme.
text: I expect such aircraft to be some specific machine that has a huge wing and low weight for other reasons, and should be recently built to benefit from latest technologies.
text: Solar impulse looks like a good candidate.
text: It has take-off speed of 35 km/h (22 mph) only.
text: Looks like
text: its minimal speed is about 20.67 mph only.
text: Its large wing holds the solar batteries.
text: It has a wingspan larger than Boeing 747 and the weight close to Cessna 172 !
text: (picture from Wikimedia Commons ).
answer_details: author: aviation.stackexchange.com/users/917/h22
score: 14
sents: text: The Ruppert Archaeoptrix Electro ( Wikipedia , official website ) apparently has a stall speed of 30 km/h (19 mph / 16 kn) , and I think that makes it a candidate for the current "slowest" fixed wing aircraft.
text: It is a relatively new glider that can be foot launched, but there are also wheeled and motorless configurations, and it can also be launched by towing. For the motorized version:
answer_details: author: aviation.stackexchange.com/users/17739/flawr
score: 14
sents: text: Gossamer Condor , the first human powered airplane capable of basic maneuvered flight.
text: When it finally won the Kremer prize for a 1 mile figure 8 course
text: it did that course in 7 minutes and 22 seconds.
text: The later Gossamer Albatross that crossed the English Channel had to be faster.
text: This assumes that the question criteria was AIRSPEED (not groundspeed) for a fixed-wing, man-carrying aircraft that could take off and land under its own power and
text: maneuver both into and out of the wind (figure 8 maneuver).
answer_details: author: aviation.stackexchange.com/users/22756/pbm
score: 14
sents: text: You should check out planes with custer wings.
text: https://en.wikipedia.org/wiki/Custer_CCW-5
text: It was claimed that the aircraft could fly under control at 11 mph (18 km/h) and that it could take off with a 1,500 lb (680 kg) load at 70% power in 90 ft (28 m).
answer_details: author: aviation.stackexchange.com/users/22771/Foo
score: 11
sents: text: Slepcev Storch
text: (A 3/4-size replica of the Fieseler
text: Fi
text: 156 Storch , a German WW2 reconnaissance aircraft well known for its slow-speed performance) 36 km/h or 40 km/h (19kn/22kn) Picture Source Performance according to Wikipedia :
text: Maximum speed: 150 km/h (93 mph; 81 kn)
text: Cruise speed: 133 km/h (83 mph; 72 kn) Stall speed: 40 km/h (25 mph; 22 kn) Rate of climb: 6 m/s (1,200 ft/min) Performance according to ulm.it : Maximum speed: 150 km/h VNE: 182 km/h Stall speed: (flaps out) 36 Km/h Climb rate: 9,1 m/s (1800 ft/min)
answer_details: author: aviation.stackexchange.com/users/790/Thunderstrike
score: 7
sents: text: I was at the Biggen Hill airshow many years ago where not one but two different aircraft flew backwards.
text: One was the AN-2 which was able to nose up into the headwind so far that it actually flew backwards for a short distance down the runway.
text: The other was a Russian super jet, (possibly a Sukhoi 27 or Sukhoi 35 ?)
text: that did a vertical climb on afterburners that shock the ground then slowed to a stop before falling on its tail while still vertical.
text: It flew tail first towards the ground before lowering the nose.
answer_details: author: aviation.stackexchange.com/users/2233/Paul Smith
score: 2
sents: text: Alaskan Bush Planes are modified to fly very slowly for short landings: Features include:"Short runway requirements, typically gained through high aspect ratio wings and high-lift devices such as flaps, slots and slats to improve low speed flight characteristics, allowing shorter ground rolls on landing or takeoff."
text: https://en.wikipedia.org/wiki/Bush_plane
text: This might be helpful too: https://en.wikipedia.org/wiki/List_of_STOL_aircraft
answer_details: author: aviation.stackexchange.com/users/22813/Gues
score: 1
sents: text: Here is a video showing that the Gossamer Albatross flew at lowest speed, 7mph (11.2kmph).
text: Very slow.
text: But the save speed will be 10mph (16.1kmph), as mentioned in that video.
text: It lasted 2 hours to cross England strait from England to France.
answer_details: author: aviation.stackexchange.com/users/34998/AirCraft Lover
score: 1

Summary of the answers:
There are a number of candidates for the slowest fixed-wing airplane. Candidates include the Antonov AN-2, the Solar impulse, Alaskan Bush planes and the Gossamer Condor.
Without there being a clear winner, the candidates that have been built with these specifications in mind are: the Gossamer Albatross, the  Antonov AN-2, Solar impulse, the Ruppert Archaeoptrix Electro, the Gossamer Condor, the  Slepcev Storch and Alaskan Bush Planes.