New Runway Design for Airplane Landing and Take-Off

[harshgoel1975]

New Runway Design for Airplane Landing and Take-Off - I Have an idea to use Gravitational force in take-off and landing of aircraft,

I have posted the idea at below link

http://www.scribd.com/doc/235525418/New-Runway-Design-for-Airplane-Landing-and-Take-Off

 

it is an innovative way to redesign runway to save much needed fuel. please comment how I can take up this to appropriate authorities, it will help mankind in long run.

[pzkpfw]

Aircraft get an advantage by taking off or landing into the wind; it decreases required ground speed.

 

With your design, different runways are needed in all directions (to have an up-slope and down-slope runway into any wind direction); whereas flat runways are a suitable "average".

 

I also don't like the idea of an aircraft landing on an up-sloping runway anyway, the approach speed in respect to the ground would start to get dangerous. (Conversely an aborted take-off on a down-sloped runway also gets harder).

 

Sorry, I don't think the idea makes sense.

Edited August 1, 2014 by pzkpfw

[harshgoel1975]

1 Aircraft get an advantage by taking off or landing into the wind; it decreases required ground speed

[HG] Can you explain , wings and craft will be parallel to each other no matter surface is incline or horizontal,

2. With your design, different runways are needed in all directions (to have an up-slope and down-slope runway into any wind direction); whereas flat runways are a suitable "average".

[HG] not at all, same runway will be used for landing and take off

3. I also don't like the idea of an aircraft landing on an up-sloping runway anyway, the approach speed in respect to the ground would start to get dangerous. (Conversely an aborted take-off on a down-sloped runway also gets harder).

[HG] thinking of something which might happen is good, but does that thinking that using LPG gas in kitchen whole house on fire is not good.great engineering require great planning.

4. Sorry, I don't think the idea makes sense.

[HG] No problem, that a good start in many way.

[Klaynos]

Most runways are already sloped due to the lay off the land. I can't see most aircraft undercarriage being able to desk with this. Have you calculated how much assistance you will provide and how many flights are required before the fuel saving equals the co2 and cost of building such a runway? People will think it looks dangerous, one of the but things in air travel is making sure everything looks and is safe.

[harshgoel1975]

This can be started as an experiment , may be for small and new upcoming airport in small cities and towns, over the period.... we would have a go no go

Any new idea should have low footprint to start with,before arriving how number of flight and ROI, COO etc detail design is needed with experts in the fields.

[CaptainPanic]

With a wind from the south, planes approach from the north (into the wind). With a wind from the north, planes approach from the south.

If your runway is sloped, you now need 2 runways in a north-south direction (one for the approach from the north, one for the approach from the south). That is the problem that pzkpfw tried to explain (I think). Since airports are generally located near large cities where ground is expensive, you suddenly need several hectares of extra space.

 

Also, it would be interesting to have an estimate of how much sand/rocks you need to create the right size hill for this idea. Take into account that it costs more than 10 euro for 1 m3 of sand to be delivered on location. The costs of such a hill/mountain could be quite high.

 

So, although I am not yet convinced that there are any real advantages in this idea, I think that the costs are going to prevent its development.

[pzkpfw]

CaptainPanic interpreted me correctly. The plan needs twice as many runways to be built. (i.e. point 2. in post #3 is not entirely correct).

 

(And probably much more than twice the overall airport land is needed, as all those uphill and downhill runways can't just be jumbled together and be safe for aircraft to use.)

 

 

Another thought is that the "uphill landing" will require stronger landing gear, as that extra force needs to be accommodated somehow.

 

That in turn means more weight carried - and while take off uses proportionally more fuel than cruising, many flights spend a long time cruising, so the cost of carrying that extra weight may well negate any advantage of the downhill take off. (Point 3. of post #3 missed the point.)

 

 

Also, I see another safety issue in the downhill take off; if the take off doesn't go well, the plane is already headed downhill - and that downhill will soon end. At least on a flat runway, there's some chance of a less severe ending to running off the end of the runway. Not always - there's been some very horrible crashes of take off - but if the craft is already heading down hill and the hill ends soon, it'll always be worse.

 

 

Sorry, the idea still makes very little sense for conventional airports.

 

 

One place where it is used in part (but reversed!), is the "ski ramp" used on British aircraft carriers to helps launch Harriers. In that case it's used only for the take off. And after the end of the runway there is generally just open sea; which would be there without the ramp in place.

Edited August 1, 2014 by pzkpfw

[studiot]

Aircraft carriers are often tilted an/or facing the wrong way.

 

I don't have the knowledge, but what we need is a pilot with carrier experience to tell us his/her thoughts.

[Cap'n Refsmmat]

Aircraft carriers are often tilted an/or facing the wrong way.

 

I don't have the knowledge, but what we need is a pilot with carrier experience to tell us his/her thoughts.

Aircraft carriers usually turn into the wind when starting flight operations.

 

The landing gear of carrier aircraft is reinforced so it will survive landing on a heaving deck.

[harshgoel1975]

definitely uphill and downhill runway has its own challenges but employing new technology ( to be developed along with)

 

And all the worst cases mention against this new approach also has limitation on conventional flat runway, E.g. Example what will happen if take off fail and flat run way end there. anyway..

 

to start with an angle of 5 degree should even help, ...

[MigL]

Small carrier based aircraft take off upslope, usually 12 deg, as this helps with rotation to a more favourable angle of incidence ( much more beneficial than incident wind speed ). See the Invincible class UK carriers, as well as the Italian carrier G. Garibaldi ( also Spanish, Brasilian and Indian carriers ). It is done to get increased range for Harriers in STOL mode. This is opposite what you propose, so I don't understand your reasoning.

Note that large carriers ( only US has them ) use steam or EM catapults.

 

Carrier based landings are done on the flat, using strengthened undercarriage to absorb high sink rates and arrestor hooks.

[Janus]

New Runway Design for Airplane Landing and Take-Off - I Have an idea to use Gravitational force in take-off and landing of aircraft,

I have posted the idea at below link

http://www.scribd.com/doc/235525418/New-Runway-Design-for-Airplane-Landing-and-Take-Off

 

it is an innovative way to redesign runway to save much needed fuel. please comment how I can take up this to appropriate authorities, it will help mankind in long run.

Anything gained on a downhill take off is lost by the plane having to climb back up again.

 

The uphill landing doesn't take in to account how landings are actually done. When you land, you approach the runway at a slope and set airspeed, upon making the runway, you cut back the engine and more or less glide in, when just above the runway you do a flare where you pull back on the stick trying to keep the plane off the runway until the plane basically does a stall and lowers itself to the runway. The stall is caused by your increased angle of attack and your lowering speed. At certain point the wing quits producing lift.

 

Now here's the thing, in your scheme the plane, in the moments before touchdown, has to be actually climbing. But a climb requires a higher angle of attack than level flight. The airspeed at which a plane stalls depends on the angle of attack. If the angle of attack increases, stall speed goes up. This means your plane trying to land on the uphill runway will touch down at a higher speed than one landing on a level one. Again, you are not really saving anything.