If winglets are fitted to, say on a Boeing 757-200, can they then be permanently removed?
As you are aware, the original Boeing 757 doesn’t come with winglets. The winglets on the plane are a retrofit meant mainly to improve its performance by reducing drag. According to Boeing, blended winglets lower block fuel and carbon dioxide (CO2) emissions by up to 5 per cent and they also improve take-off performance allowing deeper take-off thrust derates that result in lower emissions and lower community noise.
So if it is a retrofit, I believe they could be permanently removed. It is a matter of cost. Boeing or their technical representatives would be able to confirm with you on this.
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