Denis
Я люблю самолеты!
- Откуда
- Украина, Донецк
То же самое мотор Lycoming O-235-L2C 110л.с. при 2550об/мин, самолет С-152. Крейсер 75% мощности - полный газ начиная с 6000футов в стандартных условиях.
Шести цилиндровая звезда. Это возможно?
Denis
Я люблю самолеты!
- Откуда
- Украина, Донецк
Continental O-470U с ВИШ, 230л.с. при 2400об/мин. самолет с-180. давление на всасывании в подчеркнутых строках соотвествует полному открытию дросселя на заданной высоте.
Вложения
Denis
Я люблю самолеты!
- Откуда
- Украина, Донецк
Для этого необходимы обороты 100% и полностью открытый дроссель начиная с высоты 6000-7500 футов в зависимости от смеси. Мотор может неограниченно долго выдавать 100%мощности на уровне моря. Ограничение крейсерских режимов на 75% мощности связано с расходом топлива. При режимах выше этого невозможно так обеднять смесь.
Denis
Я люблю самолеты!
- Откуда
- Украина, Донецк
Смотрите внимательно. У О-200 на 7500 футах будет 2700. Все поршневые безнаддувны едвигатели при подъеме на высоту ведут себя одинаково. Максимальная мощность при 100% оборотов мототонно уменьшается в функции плотности воздуха, а поддержание крейсерского режима требует все большего открытия дросселя и все больших оборотов, вплоть до 100%.
Miklash
Дело надо делать хорошо, плохо само получится
- Откуда
- Россия-Чехия
А что-же всё таки с гармоникой не так у шести цилиндровой звезды?
Operating The Direct Drive, Fixed Pitch
Lycoming Engine
Some pilots have demonstrated a lack of understanding with regard to the operation of the direct drive, fixed pitch, normally aspirated powerplants. When a power chart is provided, it will indicate that as the airplane is flown at different altitudes above sea level, it is necessary to use higher RPM for adequate cruise performance with an increase in altitude. A typical example might be the 0-360, 180 HP Lycoming powerplant. The power chart by the airframe manufacturer for this fixed landing gear aircraft lists 75% power at 7500 feet at 2675 RPM (no manifold pressure age in their airplane). The pilot who does not understand the principles of operation in the thin air at altitude may observe that red line takeoff RPM is 2700 RPM, and is then reluctant to lean either for cruise or climb despite the altitude because he is pulling almost the same RPM as at takeoff.
However, he can and should lean the engine at these altitudes despite the high RPM, for the horsepower is down to 75% because of the thinner air. On the other hand, with any direct drive normally aspirated Lycoming engine, he can and should lean the mixture at any altitude as long as he is in cruise configuration at 75% power or less.
Let's take a look at the airframe manufacturer's power chart for the 0-360, 180 HP engine and observe the gradual increase in RPM required with the increase in altitude, but maintaining 75% for cruise at each altitude. What the chart will not show here is that for flight above 7500 feet, it is not possible to achieve 75% power with a normally aspirated engine (meaning not turbocharged or supercharged).
Altitude RPM Percent of H.P. Endurance on 59 gals. fuel
2500 2550 75% 4.8 hours
3500 2575 75% 4.8 hours
4500 2600 75% 4.8 hours
5500 2625 75% 4.8 hours
6500 2650 75% 4.8 hours
7500 2675 75% 4.8 hours
Lycoming Engine
Some pilots have demonstrated a lack of understanding with regard to the operation of the direct drive, fixed pitch, normally aspirated powerplants. When a power chart is provided, it will indicate that as the airplane is flown at different altitudes above sea level, it is necessary to use higher RPM for adequate cruise performance with an increase in altitude. A typical example might be the 0-360, 180 HP Lycoming powerplant. The power chart by the airframe manufacturer for this fixed landing gear aircraft lists 75% power at 7500 feet at 2675 RPM (no manifold pressure age in their airplane). The pilot who does not understand the principles of operation in the thin air at altitude may observe that red line takeoff RPM is 2700 RPM, and is then reluctant to lean either for cruise or climb despite the altitude because he is pulling almost the same RPM as at takeoff.
However, he can and should lean the engine at these altitudes despite the high RPM, for the horsepower is down to 75% because of the thinner air. On the other hand, with any direct drive normally aspirated Lycoming engine, he can and should lean the mixture at any altitude as long as he is in cruise configuration at 75% power or less.
Let's take a look at the airframe manufacturer's power chart for the 0-360, 180 HP engine and observe the gradual increase in RPM required with the increase in altitude, but maintaining 75% for cruise at each altitude. What the chart will not show here is that for flight above 7500 feet, it is not possible to achieve 75% power with a normally aspirated engine (meaning not turbocharged or supercharged).
Altitude RPM Percent of H.P. Endurance on 59 gals. fuel
2500 2550 75% 4.8 hours
3500 2575 75% 4.8 hours
4500 2600 75% 4.8 hours
5500 2625 75% 4.8 hours
6500 2650 75% 4.8 hours
7500 2675 75% 4.8 hours