The rules mandating a single nose tip, to be mounted far lower than previously and with a minimum cross section, were introduced for safety reasons.
The other cars that have so far been revealed have featured the 'anteater' nose, which forms the nose tip with a finger-like extension.
Lotus's twin tusk arrangement eschews this philosophy and stretches the wording of the rules to the limit.
In order to meet the single lower nose tip regulation, the two tusks are of unequal length, so the longer one forms the mandatory nose tip, while the other is short enough to avoid being considered part of the nose tip by the regulations.
This leaves each tusk to act as a crash structure, the front wing mounting pylon and then, as they slim narrow the rear of the car, also become turning vanes.
This means the unavoidable obstruction of the mandatory nose tip is made into a multi-purpose device.
The design may present slightly more total cross sectional area to the airflow, but places the obstruction in the most beneficial location.
http://www.autosport.com/news/report.php/id/112265
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