陳寬仁教授
1986年挑戰者號災難報告（也稱為羅傑斯委員會報告）指出，右側固體火箭助推器 (SRB) 接頭中一個 O 形密封圈失效是事故的直接原因。報告詳細說明了發射當天的低溫如何損壞密封圈，導致熱氣體逸出並燒穿外部燃料箱，最終導致結構性損壞和太空梭解體。該委員會還強調了 NASA 內部的組織和決策失誤，例如安全系統不足以及迫於緊迫的發射時間表的壓力，這些都是促成事故發生的因素。
您可以觀看此視頻，了解更多關於挑戰者號災難以及 NASA 忽視的警告：
- The primary cause was a failure in the O-rings sealing the aft field joint of the right SRB.
- The O-ring design was flawed, being too sensitive to cold temperatures, which prevented the seal from functioning correctly during the Challenger's cold launch day.
- The escaping hot gases from the faulty joint created a breach in the external fuel tank, leading to its eventual failure.
- The structural failure of the external tank exposed the orbiter to severe aerodynamic forces, causing the Challenger to break up.
- The commission also pointed to NASA's organizational culture, characterized by scheduling pressures, excessive overtime, and a flawed safety and decision-making process, as significant contributing factors to the tragedy.
- On January 28, 1986, the Challenger launched, but the extremely cold conditions affected the O-ring in the SRB joint.
- The O-ring failed to properly seal, allowing hot gases to leak out of the booster at the joint.
- This leak burned through the external fuel tank, causing a structural failure.
- The vehicle's structural integrity was compromised, leading to its violent breakup 73 seconds after launch.
- The accident led to a significant restructuring of the Space Shuttle program to improve crew safety.
- It prompted NASA to implement stronger safety measures and review its management and decision-making processes.
- All seven astronauts aboard the Challenger were killed, a tragic loss that deeply affected the United States and the global space community.
羅傑斯委員會報告的主要發現
機械故障：
主要原因是右側固體火箭推進器尾部密封接頭的O形環失效。
設計缺陷：
O形圈設計有缺陷，對低溫過於敏感，導緻密封件在挑戰者號冷發射日無法正常運作。
外部燃料箱破裂：
從故障接頭逸出的熱氣體導致外部燃料箱破裂，最終導致其失效。
氣動解體：
外部燃料箱的結構故障使軌道器暴露在強大的氣動載荷作用下，導致挑戰者號解體。
組織文化：
委員會也指出，NASA的組織文化，包括日程安排壓力、過度加班以及有缺陷的安全和決策流程，是導致悲劇的重要因素。
事故進展
1. 點火升空：
1986年1月28日，挑戰者號發射升空，但極端寒冷的天氣影響了助推器（SRB）接頭的O形環。
2. O形圈失效：
O形環未能正確密封，導致助推器接頭處高溫氣體洩漏。
3. 燃料箱洩漏：
洩漏燒穿了外部燃料箱，造成結構性損壞。
4. 解體：
航天器的結構完整性受損，導致其在發射後73秒劇烈解體。
報告影響
專案範圍調整：
這次事故導致太空梭計畫進行重大重組，以提高機組人員的安全性。
安全改進：
這促使美國太空總署實施更嚴格的安全措施，並審查其管理和決策流程。
機組人員罹難：
挑戰者號上的七名太空人全數罹難，這場悲劇性的損失深深影響了美國乃至全球航太界。
And when the space shuttle Challenger exploded shortly after it was launched on Jan. 28, 1986, Dr. Feynman joined the Presidential commission investigating the disaster. His co-commissioners soon found that it was hard to keep track of him.
Sometimes, with the commission meeting in full session, he would be missing. Later it would turn out that he had been conducting a private investigation, prowling around Cape Canaveral, Fla., questioning engineers and looking at the rocket boosters in storage.
1986年1月28日，挑戰者號太空梭發射後不久爆炸，費曼博士加入了調查這起災難的總統委員會。他的同事很快就發現，很難找到他的蹤跡。
有時，在委員會全體會議期間，他會失蹤。後來人們發現，他一直在進行私人調查，在佛羅裡達州卡納維拉爾角附近徘徊，詢問工程師，並查看倉庫裡的火箭助推器。
That did not sit well with the chairman, William P. Rogers, who wanted an ''orderly investigation.'' Nor did Mr. Rogers like Dr. Feynman's habit of heading for the television cameras to share his findings.
At the hearings themselves, his hair often disheveled, Dr. Feynman ambushed witnesses from the National Aeronautics and Space Administration with aggressive questioning. Then, on Feb. 11, as a piece of O ring material was being passed from commissioner to commissioner, he quietly asked for ice water.
The rubbery O ring provided the critical seal in the rocket booster, and was designed to block the escape of hot gas from the joint connecting the individual rocket segments. Its ability to perform when cold was coming under sharp scrutiny.
As Dr. Feynman expected, when he cooled the rubbery material and squeezed it with a clamp, it failed to spring back into shape. Mr. Rogers saw what was coming, and a few minutes later, at the lunch break, he turned to the astronaut Neil Armstrong and said, ''Feynman is becoming a real pain.'' Material Found Vulnerable
After the break, Dr. Feynman brought the crowded hearing room to dead silence by addressing Lawrence B. Mulloy, the former chief of the solid rocket booster program: ''I took this stuff that I got out of your seal and I put it in ice water, and I discovered that when you put some pressure on it for a while and then undo it, it doesn't stretch back. It stays the same dimension. In other words, for a few seconds at least and more seconds than that, there is no resilience in this particular material when it is at a temperature of 32 degrees.''
這讓主席威廉·P·羅傑斯（William P. Rogers）很不滿意，他希望調查「有序進行」。羅傑斯先生也不喜歡費曼醫師走到電視攝影機前分享調查結果的習慣。
在聽證會上，費曼博士經常頭髮凌亂，他用咄咄逼人的提問突襲了美國國家航空暨太空總署（NASA）的證人。然後，在2月11日，當一塊O形圈材料在委員之間傳遞時，他悄悄地要了冰水。
橡膠O形環是火箭助推器中的關鍵密封件，其設計目的是阻止熱氣體從連接各個火箭段的接頭處逸出。它在低溫下的性能受到了嚴格的審查。
正如費曼博士所料，當他冷卻橡膠材料並用夾子擠壓它時，它並沒有恢復原狀。羅傑斯先生預見了即將發生的事。幾分鐘後，午休時，他轉向宇航員尼爾·阿姆斯特朗說：“費曼真是讓人頭疼。” 材料易受損傷
午休後，費曼博士對前固體火箭助推器項目負責人勞倫斯·B·馬洛伊發表講話，令擁擠的聽證會現場鴉雀無聲：“我把從密封件中取出的東西放進冰水中，發現當你對它施加壓力一段時間後再鬆開它時，它不會回彈。它會保持相同的尺寸。換句話說，在32甚至幾秒鐘說，在32的溫度下。
Dr. Feynman and others concluded that if the space agency had conducted the same experiment and acted on the results, the disaster could have been avoided. When the commission finished its work, Mr. Rogers was barely able to prevail upon Dr. Feynman not to dissent from the report.
But he held a separate news conference to deliver a harsh and independent verdict: that NASA had ''exaggerated the reliability of the space shuttle to the point of fantasy.''
費曼博士和其他人得出結論，如果NASA進行了同樣的實驗並根據結果採取行動，這場災難本可以避免。委員會完成工作後，羅傑斯先生勉強說服費曼醫生不反對報告。
但他召開了另一場新聞發布會，發表了嚴厲而獨立的裁決：NASA「誇大了太空梭的可靠性，簡直到了不切實際的地步」。
即便如此，費曼醫師也已經開始與癌症抗爭，並於週一去世。
Even then, Dr. Feynman had begun a struggle with the cancer that killed him Monday.
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