Gates Learjet 23, 24, 25, 28 и 29
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Самыми последними вариантами первого поколения стали Learjet 28 и Learjet 29. На Learjet 28 использовали фюзеляж от Learjet 25D в сочетании с крылом с суперкритическим профилем и винглетами; первый полет состоялся 21 августа 1978 года. Построены всего пять Learjet 28. Learjet 29 - вариант Learjet 28 с увеличенной дальностью полета; построены два самолета.
Learjet 28 и 29, созданные на единой базе, имели фюзеляж Learjet 25 и крыло Longhorn с винглетами. Модели коммерческого успеха не имели, но послужили хорошей основой для создания семейства Longhorn бизнес-джетов Learjet.
This Learjet performed laminar flow experiments. There are several portions of unpainted skin sections, not an unusual appearance on testbed aircraft.
The NASA Langley organization has a number of testbed aircraft including a Cessna 402B, 172 Skyhawk, T-34C, PA-28RT, and Learjet.
One of the handful of Longhorn 28/29s delivered during 1979, before production was temporarily halted to allow maximum effort to be deployed on the Longhorn 50 series.
The Learjet Model 28/29 "Longhorns" were the first in the series wi th a wing optimised for long-range high-altitude operation.
Comparative side profiles of the Learjet prototype (note single nosewheel door); the production Model 23 and original Model 24/24B; the Model 24D/E/ F with tailplane/fin acorn deleted and tip-tanks drooped (4th cabin window on late models only); Model 25 original form; Model 28/29 Longhorn; Model 35/36 (5th cabin window on late models only) and Longhorn 50 series.
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