16
$\begingroup$

Couldn't you just generate lift with a long body? Maybe a little broader than a normal plane.

As a design enhancement, we would need a heavier bottom, so the plane doesn't flips to a side.

$\endgroup$
26
$\begingroup$

Do airplanes need wings?


Wait a minute! Airplanes have to have wings by FAA regulation, so you won't find any airplane without wings in the US.

FAA definition:

Airplane. An engine-driven fixed-wing aircraft heavier than air, that is supported in flight by the dynamic reaction of the air against its wings.

My advice here: If you encounter an airplane without wings (an unapproved case) do only your duty, call FAA immediately at 866-TELL-FAA (866-835-5322):

enter image description here
(Source)


Aircraft on the other hand has benefited from FAA's leniency, and don't have to have wings:

Aircraft. A device that is used or intended to be used for flight in the air.

As you can see, they are not required to have an engine, nor large rocks in the cargo hold to ensure they are still heavier than air. No, the only requirements for an aircraft are that:

  • At the beginning you intend to make the thing fly. It's perfectly legal to try to see if you could save wings from the bill, as long as you are honestly expecting it to fly.
  • You want it to fly in the air, not in the water, certainly not in the vacuum of the space. That's the part requiring all your attention during the design. The lift must be carefully monitored, you need to remain in this tiny layer called atmosphere, else you leave the aircraft category, and maybe the aviation field too.

This is a wingless aircraft:

enter image description here
Full scale Lippisch's Aerodyne, a VTOL aircraft built at Collins (Source)

This one is fully in the law, don't call FAA...


It's certainly a stupid answer, I did my best for, but it's correct :-)

$\endgroup$
  • $\begingroup$ He has a point. $\endgroup$ – Ryan Mortensen Jun 8 '16 at 23:53
  • 8
    $\begingroup$ You get +100 pedant points. Nice work! $\endgroup$ – Jamiec Jun 9 '16 at 15:31
  • 2
    $\begingroup$ The "aircraft" definition doesn't require that it has to be only used for (or be intended for) flight in the air. The Space Shuttle certainly was intended for flight in the air, even though it didn't remain in the atmosphere. $\endgroup$ – cpast Jun 11 '16 at 21:11
  • $\begingroup$ @cpast: Interesting! According to Wikipedia the Space Shuttle was a spaceplane: "an aerospace vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space". It seems they have anticipated all cases :-) $\endgroup$ – mins Jun 11 '16 at 22:32
15
$\begingroup$

Yes you can, these are called lifting bodies, they are not very efficient and require a lot of speed before they generate enough lift to stay aloft, requiring a long runway.

In 1983 a F-15 fighter lost a wing in a mid air collision and was able to land safely due in part by the main body being able to generate enough lift for the plane to stay controllable.

They are only really useful for supersonic flight where normal wings create too much drag

$\endgroup$
  • 1
    $\begingroup$ That f-15 story never fails to amaze me. $\endgroup$ – codedude Mar 30 '14 at 5:32
  • $\begingroup$ Saw a pic of that F-15. A couple feet beyond the wing root the wing was just ... gone. Amazing. $\endgroup$ – radarbob Apr 2 '14 at 3:03
  • 1
    $\begingroup$ Pics or it didn't happen: skeptics.stackexchange.com/questions/9884/… $\endgroup$ – Bigbio2002 May 6 '14 at 17:26
  • 2
    $\begingroup$ Although remember that the F-15 also has a >1 Thrust-weight ratio... in theory, if you could balance one properly, you could pull up vertically and reduce power which would allow could hover and land vertically on the tail. In that crash, the engine thrust was used to augment lift (along with the high speed) $\endgroup$ – Jon Story Nov 21 '14 at 12:13
10
$\begingroup$

There are indeed lifting bodies which were able to fly without wings. But wings are much better at creating lift than a bulky fuselage. The space shuttle was developed based on testing lifting bodies, which allows it to have fairly small wings.

What you are describing sounds a bit like the blended-wing-body (BWB), which smoothly integrates the fuselage with the wing. Sort of like a commercial version of the B-2 flying wing design.

enter image description here

This is certainly still in the concept phase. Boeing has flown a scale model to test the concept, and it has performed well. Aside from being more efficient than traditional designs, it can also produce much less noise if the engines are positioned above the fuselage.

We have about 100 years of development in the traditional airplane design, which contributes to the efficiency and safety that we are able to achieve right now. Going with a BWB design alters so many of the standard design features that this presents a very radical change. When the benefits start to outweigh the costs of moving to this design, we may start to see more planes like this.

$\endgroup$
  • 2
    $\begingroup$ The BWB design is interesting, but it's unlikely to ever be used in an airliner. First, this shape doesn't fit nicely into the gate systems at airports. Second, most of the passengers would have to sit too far from doors or windows to be comfortable (or to meet evacuation requirements). $\endgroup$ – fluffysheap Mar 30 '14 at 6:57
  • 2
    $\begingroup$ @fluffysheap yeah, waaaay too many middle seats in a plane like that. It is interesting how much customer perception matters. I remember watching a documentary on Boeing vs. Lockheed designing a new fighter (Lockheed won and gave us the F-35), but Boeing's design was so radical, it almost was doomed from the beginning because it didn't "look" like what a fighter "should" look like. I think the same thing applies with airplanes. In fact (and this is ridiculous), I knew someone who wanted to fly Pipers rather than Cessna singles because the Pipers "looked like a real airplane." $\endgroup$ – Canuk Mar 30 '14 at 15:06
  • $\begingroup$ Hey! More radical and absurd airplane designs: dailymail.co.uk/sciencetech/article-2538651/… $\endgroup$ – shortstheory Mar 30 '14 at 17:04
  • 1
    $\begingroup$ Saying that lifting bodies testing is what allowed the shuttle to have small wings might be a little misleading because you make it sound like the shuttle was designed using lifting body concepts, when really all they shared in common was a steep approach profile followed by a long flare. In fact, one of the reasons lifting-body research was abandoned by the US Air Force was because the Shuttle decided to go with a double-delta wing instead of a lifting body configuration. $\endgroup$ – Bret Copeland Mar 31 '14 at 0:40
0
$\begingroup$

Yes it is possible but the lift needed to lift it off the ground would be so incredible. There was one prototype plane produced by the USAF on this design. The plane was the NASA M2-F1 and it was incredible for the time. It was 20ft long and 9ft 6in tall. It had a bodyspan of 14ft 2in. The theory worked but the problem was it ran on solid rocket fuel. This resulted in a large engine and a even larger fuel cost. It only could go about 130 knots and that was on full throttle. It also only had a range of ten miles.... Yeah.

So as you can see yes this was a idea and the theory is there but we need some much better engines before it becomes practical.

$\endgroup$
0
$\begingroup$

I do not know about other airplanes, but, I can say that you can remove the wings on a Yack RC aerobatic plane and make a take off, climb to altitude, level off and perform level flight, perform barrel rolls. inside loops, Cuban 8s, and perform high rate rolls. Last you can land the plane safely. All this demonstrated on RealFlight Simulator.

There are some techniques not normally used in winged flight that must be understood and used to make this wingless flight possible.

(1) The prop's pulling vector must be high enough above level to the ground so that the lift component of the vector is larger quantity than the weight of the fuselage. Remember, the plane is very light as there are no wings. Fuselages could be built much lighter as there is no wing stress on the fuselage, and the maneuvers, excluding high rate rolls, are slow rate of turn and pitch attitude meaning g forces are much smaller and insignificant. Pulling out of a loop at the bottom is made possible by the tail pushing the back of the fuselage downward which raises the nose upward and causes the tail to fly below the axis of flight. Some of the lift for the pull up is distributed along the hull of the aircraft as wind hitting the bottom of the aircraft creates lift. This lift distribution along the entire fuselage distributes pull up g forces along the entire fuselage. Net very low g force concentration. The center of lift of a wing is outboard of the fuselage, the outboard location causing a bending moment on the wing at the attachment to the fuselage. This creates a wing breaking stress under high g forces. Also, the stress is at the point of attachment of the wing and this stress is countered by the weight of the fuselage which is distributed in front of and behind. The fuselage thus must resist the front to back centralized stress to resist breaking up at the wing junction. No such problem with the wingless aircraft.

(2) With no wings to add weight, the wingless plane can take off in very short space. The taller the landing gear (assuming a tail dragger design) the higher the angle of incidence of the fuselage and axis of propeller pull. Building taller and taller main landing gear allows the plane to take off in shorter and shorter distances to the point where if the axis of the fuselage was straight up, the plane would take off straight up. With no wing weight, the plane would climb very quickly.

(3) Until the plane's wheels leave the ground, the prop's wash and its axis of pull is in line with the fuselage, the wash hitting the elevator and rudder, the rudder's upper part above the prop's axis. Right rudder turns the plane on the ground to the right but being above the fuselage axis, right rudder also induces left roll. This roll is against the turn and causes to be vary unstable, the plane susceptible to simply rolling over on its side if the width of the landing gear is not enough to counter the roll vector. It is suggested that a wingless plane have wide landing gear for this reason.

(4) Once the wingless plane leaves the ground, the nose initially rises while the tail is still on the ground. This makes a steeper angle of the fuselage to the plane's direction and the prop wash (as seen when a smoke screen is used on the front of the fuselage) completely misses the tail sections, the wash flying over them. The axis of roll of the plane is concentric with the prop wash. Now, when the rudder is turned to the right, the vector of the rudder turns the plane to the right on the direction of flight axis. However when turning right, the rudder being below the axis of roll, induces a roll moment on the axis of flight that roles the plane to the right. In this nose up fuselage angled below the axis of flight, the rudder performs the turning function and the roll function. If the flight speed is too fast, the axis of flight and the fuselage axis close together and the rudder behave in turn in a direction opposite the rudder input. This flying with the nose too low causes loss of control and can result in extremely fast roll rates. It thus becomes paramount that the wingless plane be flown with very high nose up attitude. In level flight the speed building up will start leveling the fuselage and result in loss of control and stability. To counter this leveling off as speed builds up, simply lower the power setting. This also means that the wingless plane will not straight up as the fuselage angle to flight angle will be 0 and the rudder will cause loss of control. At the top of an inside loop, the tail will pull the tail over the top maintaining the rudder's roll and turn function.

(5) Turning: The rudder in nose high attitude will swing the nose but it will also bank the plane. Initiating right rudder will bank the wingless plane to the right. At this time, the operator simply pulls back on the elevator which causes the plane to turn similar to a winged plane, a coordinated efficient turn.

(6) Landing: A few prayers help! To lose altitude don't push the nose down with the elevator as this will cause the tail to rise up onto the prop wash creating instability and loss of control. Rather, pull back on the power maintaining full up elevator. the plane will sink at your desired speed. The plane will appear to hit hard on touchdown, but the front wheels and the tail wheel hit together or tail wheel first absorbing impact. Also, remember that the weight of the wings is absent. The plane can land at a very high sink rate without destruction of landing gear or broken fuselage. I have broken many main landing gears landing planes hard with wings. To date, I have not broken one landing gear landing many times wingless. Remember, when landing with no wings that the moment the tail and mains are on the ground, the prop wash and axis of flight are level with the rudder and the plane is prone to tipping over when rudder is actuated. Use rudder judiciously until the rolling speed has slowed down.

(7)I suggest that all aerobatic airplane have split control on the elevator. The elevator is in the prop wash and is effective in slow speed nose high flight. When right aileron is initiated, the elevator's right side will turn down slightly and the left side will turn up. This splitting could be done by putting separate servo controls on each independent side of the elevator or 2 the push-pull control servos could be run to each side of the elevator but the servos could be on attached to each other and a third servo could pull the two servos to actuate elevator function. This would give back to the airplane's operator the ability to control bank, the bank not dependent on being below the airflow of the prop and axis of flight direction of the flight.

Can the plane perform in the real world with the above modifications? I believe so. Wingless flight with split elevator would open a complete new world to freestyle RC flight. Wings could be made to be easily removable before takeoff or could be made to be dropped off during flight. Pilots could develop no wing flying skills using the RealFlight Simulators, the skills developed while going through the inevitable crashes without having to rebuild expensive equipment. Just hit the reset button!

Bottom line, the answer is a surprising YES! Below is 17 minute YouTube video I published with aerobatics and without wings:

$\endgroup$
  • 1
    $\begingroup$ This answer could be improved by using something more realistic than RealFlight, and with a video using screen capture instead of filming the computer screen. But it is an interesting discussion of the physics involved. The observations here seem mostly limited to the RC scale though. $\endgroup$ – fooot Sep 13 '16 at 14:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.