🛫 密度高度计算器（含高度表拨正、露点）Density Altitude Calculator (with Altimeter Setting and Dew Point)

使用说明与常见问题How-to & FAQ

「密度高度计算器（含高度表拨正、露点）」是什么？What is the Density Altitude Calculator (with Altimeter Setting and Dew Point) tool?

输入机场标高、高度表拨正值和气温（可选露点），先求气压高度，再按国际标准大气从空气密度求出密度高度；同时给出常用的“每高于标准温度 1 °C 加 120 英尺”经验值和 ISA 温度偏差。仅供学习，飞行请使用经批准的性能资料。本地处理。Enter the field elevation, altimeter setting and temperature (and optionally the dew point) to get the pressure altitude and then the density altitude from the air density in the International Standard Atmosphere, alongside the common 120 ft per °C rule of thumb and the ISA deviation. For learning; use approved performance data for flight. Processed locally.

如何使用「密度高度计算器（含高度表拨正、露点）」？How do I use the Density Altitude Calculator (with Altimeter Setting and Dew Point) tool?

在「密度高度计算器（含高度表拨正、露点）」中，填写「机场标高（英尺）」、「高度表拨正」、「拨正单位」、「气温 °C」、「露点 °C（可选）」等参数，结果会随输入实时计算并显示在下方。In the Density Altitude Calculator (with Altimeter Setting and Dew Point): Fill in "Field elevation (ft)", "Altimeter setting", "Setting unit", "Temperature °C", "Dew point °C (optional)"; results are recalculated instantly as you type.

密度高度是什么？What is density altitude?

密度高度是当前空气密度在国际标准大气中对应的高度。天热、气压低、空气潮湿时密度高度升高，飞机起飞滑跑更长、爬升更慢。It is the height in the standard atmosphere that has the same air density as now. Heat, low pressure and humidity raise it, so aircraft need longer take-off runs and climb more slowly.

怎么计算？How is it calculated?

气压高度 ≈ 标高 + (1013.25 − 拨正 hPa) × 30 英尺；再由气压和温度（及露点）求空气密度 ρ，密度高度 = 145442.16 × [1 − (ρ/1.225)^0.234969] 英尺。经验法则是气压高度 + 120 × (OAT − ISA 温度)。Pressure altitude ≈ elevation + (1013.25 − setting in hPa) × 30 ft. Air density ρ comes from pressure, temperature and dew point, and density altitude = 145442.16 × [1 − (ρ/1.225)^0.234969] ft. The rule of thumb is pressure altitude + 120 × (OAT − ISA temperature).

湿度影响大吗？Does humidity matter much?

有影响但较小，湿热天气通常会再增加几百英尺。不填露点时按干空气计算。Yes, but less than temperature; hot humid days typically add a few hundred feet. Without a dew point the air is treated as dry.

能举个计算实例吗？Can you show a worked example?

例如在「密度高度计算器（含高度表拨正、露点）」中填 机场标高（英尺） = 0，高度表拨正 = 29.92，拨正单位 = inHg，气温 °C = 15，结果区显示：密度高度：1 ft (0.19 m)；气压高度：0 ft；ISA 温度：15 °C；ISA 偏差：+0 °C；经验值 PA + 120 × 偏差：0 ft；空气密度：1.225 kg/m³ (100 %)；⚠ 仅供学习。起飞和爬升性能请以飞机手册和经批准的计算为准。For example, entering Field elevation (ft) = 0, Altimeter setting = 29.92, Setting unit = inHg, Temperature °C = 15 in the Density Altitude Calculator (with Altimeter Setting and Dew Point) gives: Density altitude: 1 ft (0.19 m); Pressure altitude: 0 ft; ISA temperature: 15 °C; ISA deviation: +0 °C; Rule of thumb PA + 120 × deviation: 0 ft; Air density: 1.225 kg/m³ (100 %); ⚠ For learning only. Take-off and climb performance must come from the aircraft…

哪些输入会被检查？Which inputs are validated?

「密度高度计算器（含高度表拨正、露点）」会检查这些输入——「机场标高（英尺）」、「气温 °C」：必须填写；「高度表拨正」：必须填写，须大于 0；「露点 °C（可选）」：可留空；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The Density Altitude Calculator (with Altimeter Setting and Dew Point) checks its inputs — "Field elevation (ft)", "Temperature °C": required; "Altimeter setting": required, must be greater than 0; "Dew point °C (optional)": optional; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem instead of showing a number.

有哪些选项可以调整？What options can I adjust?

「密度高度计算器（含高度表拨正、露点）」的设置：「机场标高（英尺）」默认 5000；「高度表拨正」默认 29.92；「拨正单位」可选 inHg、hPa（默认 inHg）；「气温 °C」默认 25；「露点 °C（可选）」可留空。每次生成结果都按当前设置处理。Settings in the Density Altitude Calculator (with Altimeter Setting and Dew Point) — "Field elevation (ft)" default 5000; "Altimeter setting" default 29.92; "Setting unit": inHg, hPa (default inHg); "Temperature °C" default 25; "Dew point °C (optional)" optional. The result always uses the current settings.

计算结果可以用于作业或工程吗？Can I use the results for homework or engineering?

「密度高度计算器（含高度表拨正、露点）」使用教科书标准公式（公式写在说明和常见问题中），适合学习和估算核对；涉及安全的工程设计请以规范和实测为准。The Density Altitude Calculator (with Altimeter Setting and Dew Point) uses standard textbook formulas (given in the description and FAQ), which is good for learning and checking estimates; for safety-critical engineering follow codes and measured values.

「密度高度计算器（含高度表拨正、露点）」免费吗？需要注册吗？Is the Density Altitude Calculator (with Altimeter Setting and Dew Point) free? Do I need an account?

「密度高度计算器（含高度表拨正、露点）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Density Altitude Calculator (with Altimeter Setting and Dew Point) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.