Study of a Regional Turboprop Aircraft with Electrically Assisted Turboshaft

Round 1

Reviewer 1 Report

Dear authors, congratlations to this clear presentation on a fairly complex topic. Only a small number of comments and proposed changes for a minor revision:

- line 42f: to my knowledge this refers to "FutPrInt50", not FUTRPRINT50

- line 209ff: Table 2 states that the wing is 90% composites. Is this considered in the S-HEX investigations?

- line 305: "see Table 1" instead of "Table 2"

- line 486f: while not part of this work, the chosen approach for complete harness mass is questionable: a more or less constant accessories mass is connected to a cable mass varying with cable length.

- line 534: should say "OEM and MTOM of the REG-BAS" for clarity

- for some reason Figure 9 is embedded 4 times in the paper (whenever "Figure 9" is referenced in the text)

- Table 5: it would be of interest to know about the battery power density in relation to the 2.5C quoted in line 822

- Figure A1: shouldn't the two ordinates say "Fuel burn delta vs. REG-BAS"?

- Abbreviations:
  # "EM" missing
  # shouldn't "TS" translate to "Turboshaft" rather than "Tower S"?

- References:
  # 26: conference/journal missing
  # 28: "cpacs.de"
  # 37: "Masseanalyse"
  # 43: conference/journal missing

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The submitted manuscript presents the integrated aircraft level results of the second conceptual aircraft design loop  for one of the regional platforms identified as REG-CON (REGional-CONservative) in the project IMOTHEP. The manuscript investigates and describes both propulsive and nonpropulsive electrical levels in a precise and thorough way. Top level aircraft requirements are presented together with the hybrid-electric propulsion configuration. The aircraft design methodology is explained in terms of sizing environment, laws and mission definition and system design and integration. The manuscript is very well written, Authors clearly state the objective of their research in the introduction and use of English language is flawless. The only suggestion would be to extend the discussion regarding the aircraft electrification process with respect to non-propulsive subsystems and improve the related literature review. For instance, in [Hierarchical control for generator and battery in the more electric aircraft. Sci. China Inf. Sci. 62, 192207 (2019)] and [Generalized Super-Twisting control of a Dual Active Bridge for More Electric Aircraft, 2021 European Control Conference (ECC), Delft, Netherlands, 2021, pp. 1610-1615,] different power converters are employed to control the power flow from the main generator to the battery and vice versa in the framework of the More Electric Aircraft.

Author Response

Please see attachment.

Author Response File: Author Response.docx