Airbus "has developed an aerodynamic option called the SHort AiRfield Package (SHARP) for the A320neo to improve its short field performance. SHARP is designed to increase lift at low speeds and improve takeoff and landing performance on short runways."

"A key component of the package—a Kevlar composite panel modification to the wing’s ‘Root Fillet Fairing’—allows for the improved landing performance. ... The UK team, working with their engineering colleagues in Bremen, Germany, had considered various proposals to reduce the approach speed at landing, said Airbus. The modification to optimize the airflow over the root fillet fairing panel, expected to be available as a retrofit, prove the ultimate “winner.”

Question: How can a change in wing root fairing, which looks to differ from the old fairing by no more than 12 inches at any point, significantly change runways requirements? This plane weighs more than 150,000 lbs, and the bump on the fairing is not bigger than my foot.

http://www.ainonline.com/aviation-news/ ... od-a320neo

The root fairing is very important aerodynamically. It affects airflow around a significant portion of the wing and has an effect on interference drag. My guess is that adding this bump affects the boundary layer at higher angles of attack.

What is the status of this package? I do not know the added weight, any other penalties, or how much the runway length is reduced.

Lightsaber

Starlionblue wrote:

The root fairing is very important aerodynamically. It affects airflow around a significant portion of the wing and has an effect on interference drag. My guess is that adding this bump affects the boundary layer at higher angles of attack.

An A320 wing has a span of 117 feet, and that bump does not look to be more than 1 foot. How much of the wing can this bump effect?

kitplane01 wrote:

An A320 wing has a span of 117 feet, and that bump does not look to be more than 1 foot. How much of the wing can this bump effect?

Compared with the average vortex generator that thing is huge.

Best regards
Thomas

Starlionblue wrote:

The root fairing is very important aerodynamically. It affects airflow around a significant portion of the wing and has an effect on interference drag. My guess is that adding this bump affects the boundary layer at higher angles of attack.

SAA's A300 B2K had a slat that extended out of the fuselage to close that gap for hot and high performance..

tommy1808 wrote:

kitplane01 wrote:

An A320 wing has a span of 117 feet, and that bump does not look to be more than 1 foot. How much of the wing can this bump effect?

Compared with the average vortex generator that thing is huge.

Best regards
Thomas

But wings typically don't have on vortex generator, but lots. Each one only effects the part of the wing immediately around it.

tommy1808 wrote:

Compared with the average vortex generator that thing is huge.

It is huge. But remember that vortex are paired in many numbers. This is just a more aerodynamic root fairing.

As mentioned by Starlion, the wing-root is an area of interference drag. You can achieve quite large results from small modifications in that area.

Vortex generators are used to stimulate airflow over the ailerons.

What they have done here is to delay the onset of a stall at low speeds. My money is on this aircraft having a lower stall speed than its non-modified brethren. With such a "PiP" comes more lift at lower speeds, getting the thing off the ground earlier and lowering approach speeds - both keys to shorter runway requirements.

Another reasonably easy patch (or fix) towards better balanced runway performance is to uprate the engines, which could very well be part of this offering. If not, I would say well done AB engineers for finding a solely aero solution for a known performance issue.

Balerit wrote:

Starlionblue wrote:

The root fairing is very important aerodynamically. It affects airflow around a significant portion of the wing and has an effect on interference drag. My guess is that adding this bump affects the boundary layer at higher angles of attack.

SAA's A300 B2K had a slat that extended out of the fuselage to close that gap for hot and high performance..

I couldn't find any photos of the Krueger flap and notch flap but here's the hydraulic schematic. I'll try and see if I can get a picture. If memory serves me correct, that flap and notch combination gave about 1.5 tons more lift. The bump in the op's photo is probably what they are trying to do, why the don't just add a movable piece that extends sideways as the leading edge deploys.

This device is probably acting like the leading edge extension on the F/A-18, combined with the slat extension generating a bound vortex at the wing root generating more lift at high alpha. It would not do too much in the cruise.

What would be the trade offs of the change? In other words, why would Airbus make this an option and not standard (other than being able to squeeze out more money from customers)?

VSMUT wrote:

As mentioned by Starlion, the wing-root is an area of interference drag. You can achieve quite large results from small modifications in that area.

I wonder if a small fixed cannard would help?

Balerit wrote:

VSMUT wrote:

As mentioned by Starlion, the wing-root is an area of interference drag. You can achieve quite large results from small modifications in that area.

I wonder if a small fixed cannard would help?

Even if it did, the cost of modifying the aircraft would be tremendous.

Polot wrote:

What would be the trade offs of the change? In other words, why would Airbus make this an option and not standard (other than being able to squeeze out more money from customers)?

Weight and parasitic drag are two I can think of, perhaps it's also expensive to make the part.

VSMUT wrote:

Balerit wrote:

VSMUT wrote:

As mentioned by Starlion, the wing-root is an area of interference drag. You can achieve quite large results from small modifications in that area.

I wonder if a small fixed cannard would help?

Even if it did, the cost of modifying the aircraft would be tremendous.

Well, did you not think that that modified bulge would not cost anything? There is always research and development work going on. My idea of the cannard comes from fighter aircraft.

Balerit wrote:

Well, did you not think that that modified bulge would not cost anything? There is always research and development work going on. My idea of the cannard comes from fighter aircraft.

It's just a modified bulge with a different shape from the bulge that is normally fitted in the exactly same place. Vastly different from fitting a canard, with the associated spars, strengthening and control actuators.

Pretty significant difference for the end-customer who has to pay for the conversion. One thing is more or less just a plug and play item, the other would require modifications on the level of converting a passenger plane into a cargo plane.

LH707330 wrote:

Polot wrote:

What would be the trade offs of the change? In other words, why would Airbus make this an option and not standard (other than being able to squeeze out more money from customers)?

Weight and parasitic drag are two I can think of, perhaps it's also expensive to make the part.

It will depend on the costs of the final part (weight and fuel burn). It is possible the extension could cut drag enough (via adroit vortex generation) to be worth making standard.

Airbus also wants to upsell. If this SHARP package is as good as I expect, I think by 2022 it will be standard.


Lightsaber

VSMUT wrote:

Balerit wrote:

Well, did you not think that that modified bulge would not cost anything? There is always research and development work going on. My idea of the cannard comes from fighter aircraft.

It's just a modified bulge with a different shape from the bulge that is normally fitted in the exactly same place. Vastly different from fitting a canard, with the associated spars, strengthening and control actuators.

Pretty significant difference for the end-customer who has to pay for the conversion. One thing is more or less just a plug and play item, the other would require modifications on the level of converting a passenger plane into a cargo plane.

I mentioned a fixed canard, could be as small as an angled plate riveted on, sometimes also called a strake.

zeke wrote:

This device is probably acting like the leading edge extension on the F/A-18, combined with the slat extension generating a bound vortex at the wing root generating more lift at high alpha. It would not do too much in the cruise.

The F/A-18's leading edge extension is larger than this bump, and on a much smaller plane.
The F/A-18 fly's at +30 degrees angle of attack, which is when the leading edge extension does it's best work. The A320 probably does not get about 12 degrees.
The F/A-18 has a low aspect ration wing, so more of it is affected by leading edge extension.

I don't think that's similar.

Balerit wrote:

I mentioned a fixed canard, could be as small as an angled plate riveted on, sometimes also called a strake.

It's not sometimes called a strake, it is a strake. Canards and strakes are two different things

But assuming that a strake could improve the performance, then I would agree, it would be pretty simple to fit.

kitplane01 wrote:

The F/A-18's leading edge extension is larger than this bump, and on a much smaller plane.
The F/A-18 fly's at +30 degrees angle of attack, which is when the leading edge extension does it's best work. The A320 probably does not get about 12 degrees.
The F/A-18 has a low aspect ration wing, so more of it is affected by leading edge extension.

I don't think that's similar.

They are very similar, in fact when the F/A-18 was first built it did not have them. The Airbus does not need them a very high alpha, but the aerodynamic principle is exactly the same as that or the canard you see on other aircraft.

zeke wrote:

kitplane01 wrote:

The F/A-18's leading edge extension is larger than this bump, and on a much smaller plane.
The F/A-18 fly's at +30 degrees angle of attack, which is when the leading edge extension does it's best work. The A320 probably does not get about 12 degrees.
The F/A-18 has a low aspect ration wing, so more of it is affected by leading edge extension.

I don't think that's similar.

They are very similar, in fact when the F/A-18 was first built it did not have them. The Airbus does not need them a very high alpha, but the aerodynamic principle is exactly the same as that or the canard you see on other aircraft.

No. I don't think that's right. The aerodynamic principal is not the same. On the F/A-18 the leading edge extension can spill turbulent air over a significant portion of the wing. That's because the LEX is (considering the size of the F/A-18 wing) large and far in front. The small bump right next to the A320 wing is nothing like the leading edge extension of an F/A-18.

Notice how large the LEX's on an F/A-18 are in comparison to to the wing, and how far forward.


Also, canards and leading edge extensions are different things with typically different functions. I will agree that a large canard well in front of the A320 wing might help the A320 achieve a higher angle of attack before stall, but that's not what is actually being offered.

Here is an example of a close-coupled canard, which helps the wing achieve a higher angle of attack. Notice it's well in front of the main wing, and has a significant span.

Essentially what we're dealing with is the loss of lift due to the gap between the fuselage and leading edge devices with the A320.

Some photos of canard and strakes/chines:

kitplane01 wrote:

No. I don't think that's right. The aerodynamic principal is not the same. On the F/A-18 the leading edge extension can spill turbulent air over a significant portion of the wing.

It is the same, it has the effect of generating a vortex which energises the area of the wing body join which produces the most amount of lift.

The F/A-18 is an extreme example as it needs them to perform manouvers that an airliner does not need to.

Azul and Avianca Brasil first operators: After EASA and FAA the Airbus A320neo SHARP has been certified by the Brazilian Civil Aviation Agency ANAC. Azul and Avianca will be the first two airlines in the world to contract the package. SHARP-320s will operate first from Rio de Janeiro Santos Dumont airport (SDU). Runway length at SDU: 02R/20L 1323 meters/4341 feet and 02L/20R 1260 meters/4200 feet respectively).

Airbus:
„SHARP will bring new efficiencies to Brazilian airlines operating in Rio de Janeiro’s Santos Dumont Airport (SDU), allowing them to maximize their capacity and profitability. Azul, followed shortly thereafter by Avianca Brasil, selected SHARP for their growing A320neo fleets and are the first two customers worldwide to opt for the solution package.“

I want to know the effect in flight. If it does not add drag, I think it will become standard in a few years.

Aesma wrote:

I want to know the effect in flight. If it does not add drag, I think it will become standard in a few years.

I'm very curious as to the same. The design might actually be a benefit. But is it? By cutting separation at the wing root lift is improved and should reduce drag. But I do not know the net effect.

Lightsaber

Brixerl wrote:

Azul and Avianca Brasil first operators: After EASA and FAA the Airbus A320neo SHARP has been certified by the Brazilian Civil Aviation Agency ANAC. Azul and Avianca will be the first two airlines in the world to contract the package. SHARP-320s will operate first from Rio de Janeiro Santos Dumont airport (SDU). Runway length at SDU: 02R/20L 1323 meters/4341 feet and 02L/20R 1260 meters/4200 feet respectively).

Airbus:
„SHARP will bring new efficiencies to Brazilian airlines operating in Rio de Janeiro’s Santos Dumont Airport (SDU), allowing them to maximize their capacity and profitability. Azul, followed shortly thereafter by Avianca Brasil, selected SHARP for their growing A320neo fleets and are the first two customers worldwide to opt for the solution package.“

Little expansion on that

A320neo SHort AiRfield Package (SHARP) ready for operations

November 24, 2017

A320 Family
Engineering
Innovations
4 mins read
Recent certification from the Brazilian authorities (ANAC) for Airbus’ SHort AiRfield Package (SHARP) has paved the way for operations with Avianca Brasil and Azul Airlines in the near future. The two airlines selected SHARP for their growing A320neo fleets and are the first customers to opt for the solution.

SHARP is a unique combination of aerodynamic, flight control, braking and software modifications, improving both take-off and landing capabilities of A320neos operating in complex airports. Santos Dumont is a challenging airport due its runway length of only 1,323 metres and obstacles at both ends, impacting aircraft landing and take-off performance.

SHARP is a result of a close collaboration between Airbus, its customers and engine manufacturers (CFM and Pratt & Whitney). It enhances payload capabilities for airlines which operate in complex airports, while bringing a sustainable and competitive advantage for their A320neo fleets. The key components of the package are a Kevlar composite panel modification to the wing’s ‘Root Fillet Fairing’ to enable improved landing performance and vortex generators attached to the vertical tail plane improving take-off performance.

ANAC’s certification joins those of other leading aviation authorities, the European Aviation Safety Agency (EASA) and the Federal Aviation Administration (FAA).

SHARP is available as either a line-fit or retrofit option for A320neos.

Amaya RODRIGUEZ-GONZALEZ
Head Of A320 Family Product Marketing