The paper presents a comprehensive study of a spinner-mounted single-beam LiDAR and its application for feedforward control. The authors demonstrate that the spinner-mounted LiDAR shows a higher measurement coherence bandwidth (MCB) compared to a nacelle-based single-beam LiDAR. Furthermore, they highlight that its feedforward control advantages surpass those of a nacelle-based single-beam LiDAR and may even be on par with a nacelle-based four-beam LiDAR system.

The paper is very well-written and the structure is well-organised. The subject matter is highly relevant to the readers of Wind Energy Science. I found it enjoyable to read. I have only a few minor technical corrections to share.

1. “In this work, a single-beam continuous-wave or a pulsed lidar system is simulated in the spinner of a bottom-fixed IEA 15 MW wind turbine.” - Maybe rephrase this because, from my understanding, both continuous-wave and pulsed lidar were considered in this work.
2. Page 11. “(in our case 0.025 Hz)” How did you know this number?
3. Page 11. Equation 31. Please state the assumptions. For example, it is a direct-drive design (no gearbox ratio), with no electrical conversion efficiency.
4. Page 11 Line 279. “Thus, a feedforward pitch rate θ˙FF can be calculated using the derivation of the static pitch curve (see Schlipf, 2016… )” I think in David’s work, he computed the pitch rate using the derivative (d \theta/dv) and the derivative of the wind speed, and also imposed a limit on the d\theta/dv. Did you do the same in this article?
5. Page 12. Line 297. “… for frequencies lower than 0.04 Hz …” How did you end up in this number? Can you elaborate?
6. Page 12. Equation 33 and 34. The integral bound is “t” and the variable of integration is also “t” as in the symbol “dt”, which is not right. Maybe change the differential of the variable to “d\tau”.
7. Page 12, Line 290. “…kp is the proportional gain, KI the integral gain…” Why is it that one is capitalised while the other is not?
8. Page 12 Line 290. “ΔΩ = ΩG,rated−ΩG” It should be \Delta Omega = Omega_G - Omgea_G,rated, unless the Kp and Ki are negative.
9. Section 4. This optimisation of LiDAR configuration was only conducted for one turbulence intensity? and one mean wind speed with 21 seeds?
10. Page 15. Line 366. “GΩuLL is the closed-loop transfer function from the REWS to the rotor speed,” Is the transfer function obtained from OpenFAST or just a simplified 1DOF drive-train/rotor model with the PI controller? If it’s from OpenFAST, does it include all the structural dynamics and how many system states are there?
11. Section 5. Regarding the simulation, was the LiDAR implementation considered the blockage of rotating blades in OpenFAST, which was stated as the benefit of the proposed LiDAR in the abstract? I wonder how much having a clear view (without the blockage) would influence the MCB.

The authors present a an application of a lidar assisted feedforward feedback controller where the lidar is located in the spinner before the blades of the rotor. This avoids the intermittent blockage of the rotating blade that a nacelle-mounted lidar classically have. Moreover, the authors also say that this configuration would allow to single beam lidar which would allow to scan the rotor area while rotating in the rotor. This is a significant economic advantage because single beam lidars are significantly cheaper than scanning lidar, which should be mounted on the nacelle in order to have an equivalent result.

The authors implement and adapt a well known lidar assisted feedforward feedback control strategy to this new lidar configuration for comparison to a lidar assisted feedforward feedback control strategy with a nacelle-mounted lidar and feedback only control strategy. A sensitivity analysis is conducted in order to find what is the appropriate configuration of the spinner-mounted lidar for the control strategy.

The authors eventually find out that the spinner-mounted lidar would allow significant improvements of the control performances compared to the nacelle based lidar and feedback only control strategies, for a wind speed of 18 m/s, for both continuous wave and pulsed lidars.

The article is well written and structured, and quite understandable. However, some typos are present and further explanations on various points would make the paper clearer. Several suggestions of improvements could be found below:

Line 125: It is not clear for people out of the domain what are the x, y and z axis, you might refer to figure 1 at least and tell where does the wind come from on it

Line 135: The equation is wrong, it should be 60/7.56= 8s

Line 159: I guess that you mean micrometer here, could you please make the \mu stick to the m?

Line 260: Can you explain further where this 0.025Hz is coming from?

Line 309: Can you write down explicitly the optimization that is considered here and refer to this equation

Line 322-323: The sentence “This is expected since the probe volume filtering effect becomes more influential for CW lidars the further the measurement range” is not clear.

Line 377: Rainflow is in a single word.