根据图表4.1有鸭翼的两个模型988-119和988-115的observables level为Moderate。

查阅报告，第2.4节
2.4 Observables Requirements
The purpose of this study is not to developlow observables technology, but rather to assess agility requirements impact onaircraft with varying degrees of stealth characteristics. This purpose and thesensitive nature of observables technology lead to the establishment of theobservables
requirements used in this study. For thepurposes of this study, low observables is defined as a level of observablesconsistent with the B-2, and 【moderate observables is defined as a level ofobservables consistent with the F-22】. No actual observables assessment will beconducted on the designs or reported. Observables are addressed purely as aqualitive measure and implemented by the designers to be consistent with therequirements and their experience.
本研究中使用的要求。为了本研究的目的，低可观察目标被定义为与B-2一致的可探测目标水平，【中等可探测目标被定义为与F-22一致的目标可探测水平】。对设计或报告不进行实际的可观察性评估。可探测对象纯粹是作为一种定性的度量，由设计师实现，以与需求和他们的经验保持一致。
综上，有鸭翼构型可以达成和F22相同等级的可探测水平。
PS：这篇报告对可探测水平仍然依靠设计师的经验进行判断，纯定性度量。

有链接吗

其实真相是这报告是95年出的，当时NASA是基于理论上的F22写的报告，结果F22是97年首飞后实际和理论相比过于拉胯把专家的脸给打肿了，NASA羞愧得不敢再提这事，也就没有后续的实机研究报告了，F22也在象征性服役了六年造了不到200架就赶紧停产了，怕继续丢人现眼

不管实锤了啥都是20年前的事了