May 26, 2023, ©. Leeham News: This is a summary of the article Part 14P. Airframe for lower friction drag. The article discusses in detail a Blended Wing Body (BWB) type airframe and how it reduces the wetted area and, thus, air friction drag compared to a conventional tube and wing airframe.
Last week we concluded that there were two ways to reduce the dominant drag component of an airliner, the air friction drag:
An aircraft architecture that reduces the wetted area is the Blended Wing-Body, BWB. This is the thesis of the JetZero upstart that proposes their Z5 BWB for carrying 250 passengers in Domestic two-class up to 5,000nm, Figure 1.
The passenger cabin is configured as three cabins side by side, as shown in Figure 2. We put the Z5 in our airliner performance model and looked at the drags and weights.
To do this, we used the Z5 overlaid on a Boeing 767-200 from JetZero’s website, Figure 3, whereby we could deduce the dimensions.
We could conclude that the wetted area, and thus friction drag is lower, and the airframe architecture reduces the weight of the aircraft, but with did not reach JetZero’s values of half the weight of a 767-200 to fly 250 passengers a 5,000nm sector.
With the reduced wetted area and weight and the increase in span, the drag when flying the 5,000nm sector was substantially reduced.
It makes a BWB like the JetZero Z5 a very interesting architecture if issues such as evacuation times and passenger satisfaction can be solved.