In This Issue
Summer Bridge Issue on Aeronautics
June 26, 2020 Volume 50 Issue 2
The articles in this issue present the scope of progress and possibility in modern aviation. Challenges are being addressed through innovative developments that will support and enhance air travel in the decades to come.

EES Perspective: Ethical Decision Making and the Aviation Industry

Thursday, June 25, 2020

Author: Elizabeth A. Hoppe


The discipline known as ethics concerns the study of what one ought to do. However, simply because a person knows which action is morally right does not necessarily mean s/he will actually do it. Time constraints, ­economic pressure, and human factors can all contribute to poor ethical decision making. In some industries ignoring what ought to be done has sometimes led to tragic results.

From questions of personal and corporate responsibility to impacts on the environment, ethical concerns are of vital importance in aviation. This column highlights two ethical theories that can aid in addressing such concerns. It then illustrates the application of ethics to the Boeing 737 MAX accidents, disease containment, and persistent contrails.

Two Relevant Ethical Theories

While ethical decision making is of paramount importance for any industry devoted to safety, deciding the best course of action is often fraught with difficulties. Often there is no clear-cut answer for how to act in a specific situation.

No single ethical theory can solve all moral ­dilemmas, but using ethical theory can be an important tool in addressing them. And qualitative ethical analysis can complement the rigorous quantitative risk assessment methods presented in this issue by B. John Garrick and Ali Mosleh (2020), especially given increasing reliance on autonomous systems.

Two prominent ethical theories that can be usefully applied in aviation are deontology and consequentialism.

Deontology, or Moral Duty

Deontology is associated with the works of Immanuel Kant (1724–1804), who based ethics on the concept of moral duty. He articulated a principle called the categorical imperative, which states that any personal rule or maxim that can apply universally to all rational beings becomes a moral law that is obligatory for everyone to follow.

But the categorical imperative is not always easy to apply, especially in cases where a conflict of moral duty may arise. For instance, Kant claims that both truth telling and keeping promises are moral laws. But promising to keep a secret, for example, may entail telling a lie, violating the duty of truth telling. Some critics also take issue with the lack of grey areas in Kantian ethics. Right is right and wrong is wrong, making deontology a rigid theory to apply in practice.


Rather than create moral laws based on duty, consequentialism focuses on the end results of actions to determine right and wrong. Consequentialist ethics fits in well with issues such as environmental sustainability practices where the needs of the present must consider the needs of the future.


One of the important consequentialist theories is utilitarianism, which calculates which consequences will maximize happiness. Its approach is analogous to the economic concept of cost-benefit analysis. Instead of using monetary values to weigh both sides, utilitarianism calculates the amount of happiness or pleasure versus the pain that may result from an action. If the amount of pleasure gained outweighs any pain involved, then the action is morally right.

However, as with other ethical theories, consequentialism has drawbacks. In maximizing happiness, the ends justify the means. But should motives not play a role in determining whether an action is morally justi­fied? Another problem is that the results may very well entail that some suffer for others to prosper. The suffering of the few would be morally allowed under utilitarianism. Finally, by focusing only on end results, utilitarianism leaves out consideration of important factors such as a decision maker’s character and/or motives.

Anticipatory Technology Ethics

Keeping in mind that no ethical theory can fit every circumstance, one form of consequentialism, anticipatory technology ethics, is especially important for science and technology as it deals specifically with the potential social consequences of emerging technologies. It can be defined as “the practice of using the design phase to reflect upon how a system or technology’s affordances will impact their use and potential con­sequences” (Shilton 2015, p. 1). It has also been explained as “the study of ethical issues at the [research and development] (R&D) and introduction stage of technology development through anticipation of possible future devices, applications, and social consequences” (Brey 2012, p. 1).

At the R&D stage ethical issues may be unknown since the technologies are not yet in use by society at large, but efforts to uncover potential ethical ­dilemmas at this stage can help prevent ethically undesirable outcomes. Futures studies are one way to determine possible ethical conflicts that may arise with new technologies under development (Brey 2012). But forecasting impacts can be uncertain, so this approach to ethics cannot cover all issues that may arise in aviation, such as persistent contrails, discussed below.

Applying Ethical Theory to Aviation

The Boeing 737 MAX

With any aircraft accident there are multiple factors that cause the crash. According to one account of the October 29, 2018, Lion Air crash, “it was caused by a combination of an improperly aligned angle of attack (AOA) sensor, lack of pilot reporting and training as well as a breakdown in safety oversight of certification and design flaws shared between Boeing and the FAA within the aircraft’s maneuvering characteristics augmentation system (MCAS)” (Bellamy 2019).

Anticipatory technology ethics could have helped forecast some of the factors in the Boeing 737 MAX accidents. Although some commentators placed blame for the Lion Air crash solely on the Boeing Company, other factors presented in the final accident report included inadequate pilot training. The need for appropriate pilot training could have been forecasted by using anticipatory technology ethics, which would have called for consideration of how the new technologies—­including MCAS—in the 737 MAX would impact pilots unfamiliar with them. Had there been more emphasis on pilot training on those new technologies, the Lion Air accident might not have occurred.

Anticipatory technology ethics is also relevant to the practice of human-machine teaming, described by J-P. Clarke and Claire Tomlin (2020, p. 46). They explain that “the role of and relationship between humans and machines are optimized based on their individual and collective capabilities,” adding that such teamwork “is critical to achieving safe and efficient (economic and environmental) operations.”

Two lessons from the Boeing 737 MAX accidents are that, to achieve this optimal level of teamwork, (1) the automated agent needs to be functioning correctly, unlike the improperly calibrated AOA sensor on the Lion Air aircraft, and (2) the human agent needs to have sufficient knowledge of how the automation operates. In the case of the Lion Air accident, one set of pilots knew how to deactivate the MCAS technology while the other crew tragically lacked the knowledge necessary to regain control of the aircraft.

Air Travel and the Spread of Disease

Another important example of how anticipatory ethics may apply to aviation concerns the role of aircraft in carrying disease. Prior to the covid-19 outbreak research had already shown that diseases spread onboard aircraft. Analysis of data related to US air travel and the incidence of influenza from 1996 to 2005 found that commercial air travel in November was a significant predictor of influenza spread (Kolmes 2019b). However, the same analysis showed that “airline restrictions would do little to slow the spread of the disease unless most air travel were to cease immediately after the beginning of the epidemic spread was detected” (Kolmes 2019b, p. 268). This finding eerily presages the covid-19 pandemic in which flight service from China was suspended too late to prevent the rapid spread of the novel coronavirus.

Given the unlikelihood of restricting air travel in a timely manner, anticipatory ethics can be a helpful tool for creating other measures. Protective measures might include preventing people with infectious diseases from boarding a commercial aircraft, increasing cabin ventilation in regions with disease outbreaks (although this would increase fuel demand), carefully disinfecting aircraft between flights, and requiring commercial aircraft to have high-efficiency particulate air (HEPA)–filtered ventilation systems (Kolmes 2019b). These suggestions were published before the covid-19 pandemic, revealing the possibility of effectively forecasting future concerns to guide decision making both at the design stage and in operations.

Persistent Contrails and the Environment

While anticipatory technology ethics can aid in decision making in the above-mentioned cases, it cannot solve all problems associated with aircraft design. One such issue concerns persistent contrails, which occur in certain conditions when aircraft are flying at altitudes of 33,000–35,000 feet and when atmospheric humidity and temperature produce ice crystal formation in the exhaust (Kolmes 2019a).

Although usually short-lived, under some ­atmospheric conditions contrails can spread and last for long ­periods, forming cirrus clouds with a heat-trapping effect. But different modeling approaches produce different estimates of the contrails’ contribution to global warming (Kolmes 2019a). This example illustrates a challenge of applying consequentialist approaches such as anticipatory technology ethics. Namely, what are the best ­decisions to make when the potential impact is uncertain and the results are unclear?

The example of persistent contrails highlights the need for applying other ethical theories, such as ­deontology. A deontologist would be concerned with the moral responsibility to address the problem by emphasizing duty rather than consequences, in considering which actions apply universally. Assuming that one of the universal moral laws would be that humans have a duty to protect the environment, then at a minimum deontology would call for seeking solutions to the problem of persistent contrails regardless of the uncertainty surrounding their level of impact on climate change.

Much research remains to be done on this topic, and the ability to determine which actions to take is problematic at best. However, persistent contrails are an important topic for anyone concerned about the impact of aircraft on the climate. In this issue Alan Epstein (2020, p. 12) states that “aviation’s most pressing challenge is climate change.” Persistent contrails contribute to climate change, so environmental ethics needs to address this matter in addition to other important ­topics such as alternative fuels and carbon offsets.

Concluding Remarks

Commercial aviation is a complex industry that requires strong ethical decision-making skills to maintain ­safety. While no one ethical theory can solve all moral ­dilemmas, the application of various theories may aid in the decision-making process. The above-mentioned examples show how ethics can help in the development and use of new technologies in ways that promote both safety and the environment. The incorporation of ethical theories can point to new methods for addressing the challenges that confront the aviation industry.


Bellamy W III. 2019. Lion Air 737 MAX final accident report cites AOA sensor, MCAS among multitude of contributing factors. Avionics International, Oct 28.

Brey PAE. 2012. Anticipatory ethics for emerging technologies. Nanoethics 6:1–13.

Clarke JPB, Tomlin CJ. 2020. Some steps toward autonomy in aeronautics. Bridge 50(2):43–50.

Epstein AH. 2020. Aeropropulsion: Advances, opportunities, and challenges. Bridge 50(2):8–14.

Garrick BJ, Mosleh A. 2020. Embracing the risk sciences to enhance air travel safety. Bridge 50(2):34–42.

Kolmes SA. 2019a. Greenhouse gas emissions, persistent contrails, and commercial aviation. In: Ethical Issues in Aviation, 2nd ed, ed Hoppe EA. London: Routledge.

Kolmes SA. 2019b. Ground-level pollution, invasive species, and emergent diseases. In: Ethical Issues in Aviation, 2nd ed, ed Hoppe EA. London: Routledge.

Shilton K. 2015. “That’s not an architecture problem!”: ­Techniques and challenges for practicing anticipatory technology ethics. iConference 2015 Proceedings.

This column is produced in collaboration with the NAE’s Center for Engineering Ethics and Society to bring attention to and prompt thinking about ethical and social dimensions of engineering practice.

About the Author:Elizabeth Hoppe is an instructor in philosophy at Loyola University Chicago.