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The special daytime echoes, which present the V‐shaped echo pattern between 90–180 km ranges in the range‐time‐intensity (RTI) plot, were occasionally recorded by the Hainan coherent scatter phased array radar (HCOPAR) located at the low latitude of China. Four cases with distinct echo traces are presented to display the common characteristics of the V‐shaped echoes. They usually occur between 10:00–15:00 LT in the daytime with the enhanced top frequency and blanketing frequency of Es layer (ftEs and fbEs). Their left/right wings present negative/positive Doppler velocity. A case on 16 August 2015 was investigated by the joint observation of the HCOPAR, the Hainan Digisonde, and a scintillation receiver. The echo spectra show that the V‐shaped echoes were backscattered from the type 2 irregularities. The formation of the V‐shaped echo pattern was due to the leakage of the antenna sidelobe for the very intense scatter from Es layer. The irregularities were found traveling westward with the velocity of 41.12 ± 2.08 m/s. While the occurrence of the intense irregularities, there were periodic peaks appearing on the ftEs and fbEs curves, and the maximum ftEs‐fbEs reached 10.31 MHz. At the same time, the strong ionospheric scintillation event was recorded by the scintillation receiver. The wind shear is considered to produce the sharp density gradient in the Es plasma and then induce the gradient drift instability. The large‐scale gravity waves have the possibility to induce the E‐region wind shear.

Sporadic-E (Es) between 90 and 120 km is a very special layer of Earth's ionosphere. It is considered as a sporadic concentration of the E-layer plasma into thin layers of high electron density (Mathews, 1998;Whitehead, 1989). It is believed that the wind shear together with the Earth's geomagnetic field compresses the E-region ions into a thin, ion-rich layer, approximately one to two km in thickness (Chu et al., 2014;Cosgrove & Tsunoda, 2002). The steep density gradient in Es creates a favorable environment for gradient drift instability, which is widely believed responsible for the E-region Field-Aligned Irregularities (FAIs) (Ecklund et al., 1981;Kagan & Kelley, 1998;Larsen, 2000). The earliest report of the scattered echoes from E-region FAIs was published in the middle of last century (Bailey et al., 1955). When the Quasi Periodic (QP) scattered echoes from Es layer were recorded by the MU radar (Middle and Upper Atmosphere Radar) in 1989 (Yamamoto et al., 1991), these plasma structures aligned along the geomagnetic fields have drawn a lot of attention of the space physics community. And then the observations of the FAIs were widely carried out all over the world (e.g.,

Sporadic-E (Es) is a comparatively strong and protracted transmission returned from the E region of the ionosphere by some mechanism other than the normal reflection process from the daytime E layer (Smith, 1957). It is produced accidentally and becomes active at any time of the day or night. It seems that the photochemical process does not dominate the formation of Es (Whitehead, 1972). Solar eclipse provides a very unique opportunity to study the responses of the ionospheric Es to the rapid solar radiation variation.The responses of ionospheric F-layer to solar eclipse is predictable (