طائرة فضائية

Space Shuttle Discovery

الطائرة الفضائية spaceplane، هي مركبة تعمل كطائرة في الغلاف الجوي للأرض، وتعمل أيضاً كمركبة فضاء عند تواجدها في الفضاء. وتجمع بين خصائص الطائرة والمركبة الفضائية، ويمكن اعتبارها طائرة يمكنها تحمل والمناورة في فراغ الفضاء وفي الوقت نفسها مركبة فضاء يمكنها الطيران مثل الطائرات. عادة، تأخذ الطائرة الفضائية شكل المركبة الفضائية المجهزة بالأجنحة، مع تعديل واختبار الأجسام الرافعة. يتم دفعها للفضاء بواسطة صاروخ يعتمد على أو بمساعدة محركات هوائية.

Four examples of spaceplanes have successfully launched to orbit, reentered Earth's atmosphere, and landed: the U.S. Space Shuttle, Russian Buran, U.S. X-37, and the Chinese Shenlong. Another, Dream Chaser, is under development in the U.S. As of 2024 all past and current orbital spaceplanes launch vertically; some are carried as a payload in a conventional fairing, while the Space Shuttle used its own engines with the assistance of boosters and an external tank. Orbital spaceflight takes place at high velocities, with orbital kinetic energies typically greater than suborbital trajectories. This kinetic energy is shed as heat during re-entry. Many more spaceplanes have been proposed.

At least two suborbital rocket-powered aircraft have been launched horizontally into sub-orbital spaceflight from an airborne carrier aircraft before rocketing beyond the Kármán line: the X-15 and SpaceShipOne.

 مبادئ التشغيل

Landing of مكوك فضاء أتلانتس, a crewed orbital spaceplane

Spaceplanes must operate in space, like traditional spacecraft, but also must be capable of atmospheric flight, like an aircraft.

Spaceplanes do not necessarily have to fly by their own propulsion, but instead often glide with their inertia while using aerodynamic surfaces to maneuver in the atmosphere during descent and landing. The U.S. Space Shuttle for instance, could not fly under its own propulsion but used its momentum after de-orbit to glide to the runway destination.

These requirements drive up the complexity, risk, dry mass, and cost of spaceplane designs. The following sections will draw heavily on the US Space Shuttle as the biggest, most complex, most expensive, most flown, and only crewed orbital spaceplane, but other designs have been successfully flown.

 الإطلاق إلى الفضاء

مكوك فضائي ينطلق في افضاء بعد انفصاله عن الصاروخ الحامل.

The flight trajectory required to reach orbit results in significant aerodynamic loads, vibrations, and accelerations, all of which have to be withstood by the vehicle structure.

If the launch vehicle suffers a catastrophic malfunction, a conventional capsule spacecraft is propelled to safety by a launch escape system. The Space Shuttle was far too big and heavy for this approach to be viable, resulting in a number of abort modes that may or may not have been survivable. The Challenger disaster demonstrated a lack of survivability on ascent.^{[بحاجة لمصدر]}

 بيئة الفضاء

Once on-orbit, a spaceplane must be supplied with power by solar panels and batteries or fuel cells, maneuvered in space, kept in thermal equilibrium, oriented, and communicated with. On-orbit thermal and radiological environments impose additional stresses. This is in addition to accomplishing the task the spaceplane was launched to complete, such as satellite deployment or science experiments.^{[بحاجة لمصدر]}

The Space Shuttle used dedicated engines to accomplish orbital maneuvers. These engines used toxic hypergolic propellants that required special handling precautions. Various gases, including helium for pressurization and nitrogen for life support, were stored under high pressure in composite overwrapped pressure vessels.^{[بحاجة لمصدر]}

 Atmospheric reentry

المقالة الرئيسية: Atmospheric entry

Buran spaceplane rear showing rocket engine nozzles, attitude control thrusters, aerodynamic surfaces, and heat shielding

Orbital spacecraft reentering the Earth's atmosphere must shed significant velocity, resulting in extreme heating. For example, the Space Shuttle thermal protection system (TPS) protects the orbiter's interior structure from surface temperatures that reach as high as 1،650 °C (3،000 °F), well above the melting point of steel. Suborbital spaceplanes fly lower energy trajectories that do not put as much stress on the spacecraft thermal protection system.

The Space Shuttle Columbia disaster was the direct result of a TPS failure.

 Aerodynamic flight and horizontal landing

Aerodynamic control surfaces must be actuated. Landing gear must be included at the cost of additional mass.

 Air-breathing orbital spaceplane concept

An air-breathing orbital spaceplane would have to fly what is known as a 'depressed trajectory,' which places the vehicle in the high-altitude hypersonic flight regime of the atmosphere for an extended period of time. This environment induces high dynamic pressure, high temperature, and high heat flow loads particularly upon the leading edge surfaces of the spaceplane, requiring exterior surfaces to be constructed from advanced materials and/or use active cooling. Skylon was a proposed spaceplane that would have used air-breathing engines.

 الطائرات الفضائية المدارية

 X-37

This section is an excerpt from بوينگ X-37.[تحرير]

إكس-37بي معدة للإطلاق.

{|

|} بوينگ إكس-37، هي مركبة فضائية غير مأهولة أمريكية الصنع. تشغلها القوات الجوية الأمريكية في مهمات فضائية مدارية بهدف اختبار تكنولوجيا رحلات الفضاء المستقبلية..

في 27 أغسطس 2019، سجلت الطائرة الفضائية الأمريكية إكس-37 رقماً قياسياً جديداً بقضائها أكثر من 717 يوماً في المدار. وفي 27 أكتوبر 2019، سجلت بوينگ إكس-37 بي رقماً قياسياً جديداً بعد قضائها 780 يوماً في المدار.

 الوصف

هبوط مكوك الفضاء أتلانتس، التابع لناسا. كانت مكوكات الفضاء الأمريكية، طائرات فضائية مدارية مأهولة.

 الرفع الهوائي

المقالة الرئيسية: رفع (قوة)

 هبوط الطائرة

المقالة الرئيسية: هبوط § طائرة

 الدفع

Buran orbiter rear showing rocket engine nozzles, for maneuvering in low Earth orbit and thin air

 محركات دفع الهواء

المقالة الرئيسية: محرك نفاث دافع للهواء

 طائرات فضائية طائرة

World's first spaceplanes — North American X-15, Space Shuttle, Buran, SpaceShipOne, Boeing X-37. The X-15 reached space in 1962/1963 (USAF/FAI Kármán line classifications). SpaceShipOne was piloted by the first commercial astronaut. Both X-15 and SpaceShipOne ascend horizontally from a mother ship. Both Buran and X-37 spaceflights were unmanned. The X-37 launches atop Centaur and Atlas V (version 501) rockets.

 طائرات فضائية تحت مدارية

المقالة الرئيسية: طائرة فضائية تحت مدارية

The X-15's rocket engine used ammonia and liquid oxygen.

 مشروعات أخرى

United States Gemini spaceplane concept testing, August 1964.

 الولايات المتحدة

United States STS Space shuttle concepts circa 1970s

Boeing X-37B being prepared for launch in 2010 on an expendable orbital rocket

 طائرة الفضاء الوطنية

إقلاع طائرة فضائية تابعة لناسا.

 الاتحاد السوڤيتي وروسيا

Buran orbiter being transported via An-225

 ألمانيا

F-104G ZLL at Luftwaffenmuseum der Bundeswehr, Berlin Gatow, for Zero length launch

 كوريا الشمالية

Mockup of NK spaceplane at Mangyongdae Children's Palace

 انظر أيضاً

• جائزة أنساري العاشر
• قائمة مركبات الفضاء المأهولة
• قائمة شركات مركبات الفضاء الخاصة#مركبات نقل الطواقم والشحنات
• مركبة فضاء

 المراجع

Hacker, Barton C., and Grimwood, James M. On the Shoulders of Titans: A History of Project Gemini, 1975. Published as NASA Special Publication-4203, 1977.

 وصلات خارجية

• Encyclopedia Astronautica article on Uragan / Zenit
• Russianspacweb: Russian Reusable Spacecraft
• Popular Science article: Space Shuttle proposals written by Wernher von Braun - July 1970
• Popular Science article: VentureStar, X-34, MAKS, Burlak and other - October 1996
• Popular Science article: Space Access' Space Plane - January 1998
• Popular Science article: Space planes - May 1999
• Popular Science article: Space plane replacement of Space Shuttle and info on past designs including NASP and Clipper - May 2003
• MSNBC - Classic design inspires futuristic space glider