This is an idea I just came up with that will hopefully solve London Heathrow's problems regarding the construction of the third runway (located north of the main airport).

--Current runways:
9L / 27R
9R / 27L

--After third runway:
9L / 27R (new)
9C / 27C
9R / 27L


--Conditions:
Runway 9L / 27R will be for landing only (of aircraft no larger than a 757-200).
Runway 9L / 27R will be 8,000 feet long, and no aircraft using the runway will be allowed to use reverse thrusters*.
Runway 9C / 27C will be for take off only (all aircraft).
Runway 9R / 27L will be for landing only (of aircraft larger than a 757-200 (reverse thrusters allowed)).
The number of takeoff/landing slots at Heathrow will not be increased from the present number for another ten(10) years.

--Benefits:
-Safer operation. Aircraft landing slots will not be so close together. Also, the two landing runways will be further apart.
-Lower pollution. Aircraft will not have to hold pattern over London. (up to 20 minute decrease in flight time)
-Lower noise over London city. Aircraft will not have to hold pattern over London.
-Lower noise near London Heathrow. All aircraft smaller than the 757 (over 40% of all flights) will not reverse thrust*.
-A third runway will be in use. If an accident occurs on one runway, flights will not be delayed.
-Future slot increase ability. In ten(10) years, overall aircraft noise will be lower, due to quieter planes. Overall aircraft pollution will be lower due to more efficient planes. Thus, the environmental consequences of increasing slots will be significantly lower.
-Pleasing London's environmental groups. This third runway will do nothing but lower noise and pollution. No negative effect.



* (Small aircraft landing on a 8,000ft. runway will not need reverse thrusters.)
* (Better spaced out landing slots will give aircraft more time to exit runway.)


If BAA builds the third runway with these conditions, they really have nothing to loose. I don't think they can do it without such drastic restrictions.