The Human Factor

pendent, human information-handling biases.² Prop¹

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The person inside the helmet has often been neglected in the headlong rush to field new hardware. To get the most from technol­ogy, we need to incorporate human skills in the design process.

Machines don’t think. Despite the hyperventilation over artificial intelligence, satellites, and super­conductivity, people, not computers, will ulti­mately determine the outcome of tactical engagements. Combat system designers need to seriously consider human capabilities. It’s called human factors engineering. Don’t worry if you don’t know what it is; most designers, engineers, and program managers don’t either.

The Department of Defense considers new technology to be the cure for just about any ill that exists in the operat­ing forces. Yet, the hasty introduction of technology over the years has made the job of operating and maintaining those new systems an overwhelming burden. New tech­nology of the next decade will not benefit the operating forces to the fullest extent unless the procurement estab­lishment implements it with human capabilities in mind.

Congress has decided that it wants “more” technology in the Seawolf (SSN-21) to the tune of more than $200 million in fiscal years 1988 and 1989. Unfortunately, the budgeting and procurement process will not support the infusion of technologies with very short half-lives. Con­sider, however, one historian’s quoted observation: “The lesson of the Falklands was that a determined pilot in an obsolete airplane with mostly obsolete weapons can sink a ship.”¹

Frequently, the disenchantment with new systems is not with the new technology but with the human interface with that technology. Interface design has been neglected in the headlong rush to implement new hardware capabilities.

Engineers have to realize that implementing new techn° ogy is more than bolting on or cabling up new systems tn just make the operator’s job harder to do.

The Role of Digital Systems: The purpose of a comb* system is to provide sensor information to humans ¹¹¹ usable format. A basic consideration is whether the ope^ra tor can assimilate the data easily. As we approach sens¹- and sound quieting parity, the primary thrust in di£| systems design should be to improve the communicah of information from machine to man. Interface d^eS’^e must no longer be subordinated to engineering concem^s’

Entrenched procedures dictated by the inadequate sy^s terns of the past also tend to inhibit anything but increm^el1 tal changes in overall design philosophies. Computer d¹ play design is more cognitive psychology than engineer¹ » or computer science. Perhaps that is why an engineer¹¹¹^ based procurement establishment is finding its meth° for hardware design inadequate for software. A mis^c0j| ception exists that software is easier to build than hm ware or is somehow less important. Hardware eim works or it does not. Software may work but still not p¹ vide the functional utility to get the job done. Desig⁰^ should not continue to regard computer displays as r another rectangle on a system block diagram. To the oP^e ator, the system is the display.

The increasing complexity of ships, planes, and we^af ons continues to reduce human reaction times and the ceptable margin for error. Better digital combat ^sY^ste should allow the operator to exercise his judgment lofl£ ' since a computer display is both external memory f°^r user as well as a communications medium.

The most important aspect of the digital combat sys^te ^ beyond its speed, capacity, and accuracy, is that it ^c . mitigate human information-handling biases. Man is m^u better at making decisions than handling data. One searcher cataloged 27 different, but not necessarily ¹¹¹ - implemented display designs can reduce human p^e

d_at ^Ce degradation by supporting the decision maker as •iir**^{rates or} tactical situation changes. Automated fea- r_eD)^{s Car}> also be used in conjunction with, instead of as tn_a foments for, human operators to provide a bench- p for comparison.

rt|_a ^at.^Ure combat systems should not hamper the com- Uj, ^,ng officer’s decision-making capacity by imposing t>ave^CeSSary datu-handling overhead. The CO should not Sg_r ^to fight his own combat system as well as his adver- t^t' Current systems are so much better than earlier ones in, ^Users and management may be unaware of potential °^veinents. Our people on the deckplates have to do the job with whatever they have. A CO cannot refuse to go to sea because he does not like his combat system.

If there are not enough people, time, and facilities for training, then designers must make combat systems easier to operate. What masquerades as tactical team training is actually phone talking and practice in equipment opera­tion. Four-hour team training sessions may contain two minutes of real tactical training scattered throughout the critique periods. Systems that impose overriding commu­nications requirements and require extraordinary amounts of hands-on time for training must be improved. Anyone who doubts there is a problem does not have recent opera-

''^am J. Perry, then-Under Secretary of Defense for search and Engineering, stated before the Senate

Services Committee on 14 March 1979:

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cycles caused by the nominal three-section watchbill fatigue caused by atmosphere control limitations,

jonal experience. Designers and purchasers must ignore **^e Problem because they think humans are flexible Enough to overcome any system inadequacies, or, alterna- '^Vety> that an infinite amount of training can offset even ^e worst system design features.

Procurement and Design Practices: The fundamental ^akness in current combat systems procurement is the ^ack of adequate definition of the user’s functional require­^ments. User involvement must be more than input to skel­^etal specifications or subjective periodic review. Dr. Wil-

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A dangerous communications gap has developed be­tween the developer of systems and the user. This gap ^has led to systems that are largely technology driven ^a°d are poorly united to the operational need because the user did not know how to state his need in terms of available technology.”³

Vone who thinks this gap has improved in the last eight j!^ears must also think that the vaunted paperwork reduc- ^l0? initiative has been noticed on the deckplates.

^rhe common philosophy is that only combat can over- _n^ress the operator. As a result, the design process usually fleets operator stress and denies the existence of Astern-induced human errors. The peacetime environ- _e ^ent creates plenty of significant operator stresses, how- ^er- Data rates created by better communications and ^nsor technologies certainly give the operator an informa- ₍ °ⁿ °verload. Merely having to use a CRT (cathode-ray . ^ci system creates operator fatigue. Factor in interrupted

f dre daily stresses on the operator create an imperative ^r better combat systems design in the peacetime environ- „ ^er|t- The traditional procurement establishment usually Aiders these concerns tangential or esoteric since their ₀j.^IrPary concerns are delivery deadlines and costs instead Astern effectiveness.

^ ^nce engineering and programming tradeoffs are made, j^ I'mit the range of supportable system features. Once Plemented, the effects of constrained capabilities are y compounded by a lack of systems integration. In ^ ^er to create an effective system, detailed user input £^Ust occur before major engineering tradeoffs are made. °ⁿtinuous user involvement during the evolution of the [, ^stem is also needed to adjust to changes that might alter ^e User’s needs.

_a ^{ne resea}rcher proposes three design principles: early continual focus on users, empirical measurement of , ^a8e, and iteration of the design. These are not inherently _Se ^uAive to designers even though they seem like common |j ^Sc- Interviews with designers have given insight into t|₁'^v ^ey work. Some designers believe they are doing d, ^Se        when they actually are not. They undervalue

f_Q|.^Se Principles because they do not believe they are worth d_le°^vving, confuse them with similar ideas, underestimate Value of interaction with users, use competing ap­proaches, or think they are impractical.

Then there is the old chestnut that users do not know what they need. Many users have never considered alter­native or improved ways of doing their job and are un­aware of options available for new designs. They do, how­ever, possess the knowledge and experience about the tasks they have to perform, the threat, and weapon- employment constraints.

Another researcher discusses the reliance upon design­ers’ intuition about the user and the tasks. Presented with experimental data, designers were unconvinced that they could build a system that people would have trouble with until they saw videotapes of the experiments. By the time they accepted the experimental results the hardware design was frozen.⁴

In the design of digital combat systems, the program­mer is the one who ultimately must implement design re­quirements. Specifications are dropped on his desk, and he is given a deadline for review or delivery. No matter how much time and effort are put into the preparation of specifications, they do not give the programmer a com­plete or detailed enough picture. He immediately has hun­dreds of questions regarding implementation. He must ei­ther take the time and effort to find answers to these questions or more likely do the best he can on his own. Some of his decisions will have profound effects on the functionality of the overall system. Inevitably, as a result of review meetings held four to six weeks later, the pro­grammer will have to recode his work or the impacts of his decisions will be overlooked. Programmers are not artists, linguists, or psychologists, nor should we expect them to be. A user-programmer team could shorten development time by eliminating recoding of the same effort several times. This time savings would then provide time for user experimentation without affecting the delivery date.

The Need for Experiments: The usefulness of highly specialized displays can only be determined with experi­ments. Historically, there has been a great deal of diffi­culty in defining measures of performance in individual decision making. Each situation has a hierarchy of mea­sures of effectiveness. These characteristically take the form of abstract products of probabilities normally used in systems design and war-gaming but offer little help in in­terpreting experimental results.

Real-time man-in-the-loop experiments are the key to performance effectiveness testing. Experiments have shown that subjective user preference is unreliable be­cause subjective ratings by subjects contradicted experi­mental results.⁵ Subjects have shown a preference for the sharpest display resolution even when it yielded the poor­est visual performance.⁶

In a Proceedings article, researchers from the Naval Submarine Medical Research Laboratory concluded that redundant shape coding of threat levels, in addition to color coding, provided no increase of performance in the assigned task.⁷ In fact, for specific target identification tasks they concluded that shape coding interfered with per­formance. One might conclude then that shape coding is useless. Consider, however, similar results from an exper-

Visual momentum becomes even more complicated with the linking and timing of multiscreen display arrange­ments. Humans are used to integrating real-world sequen­tial scenes into a complete visual picture of the world. Sequential displays are 50% faster than simultaneous dis­plays because of the elimination of eye movements. These sequential displays operate on the same principle as the subliminal popcorn ads outlawed in theaters. Sequential displays also use less space and can provide optimum data sampling in changing situations. Sequential displays that overlap yield better results than continuous scanning of a single large display. Selective call-up filters can be used with sequential displays to unclutter them when informa­tion density becomes too much to handle.

One critically neglected area is the incorporation of the auditory data channel to reinforce visual presentations. Characteristically, engineers have used auditory functions to specify intrusive alarm conditions. As a result, the user is unwilling to consider such features in future systems. Submariners are particularly well suited to using the audio channel. Countless hours of looking through a periscope have conditioned the submariner to sense occurrences in the control room with his ears. Verbal reports, audio alarms, early warning receivers, switches, fans, and hy­draulic noises all tell the officer-of-the-deck what is going on, in addition to his keyhole look at the outside world.

Some simple enhancements could also be incorporated into engineering displays. Gauges in race cars are oriented so the indicator needles are vertical when the readings are normal. The drivers do not read the gauges; they quickly scan the dashboard to see if anything is wrong. Extend this concept to the control panels of a nuclear power plant with a hundred or so gauges for the operator to read, and holis­tic data presentation makes a lot of low-tech sense. Inte­gral or object displays for power plant data can be used to remove a sequential data presentation bias. Experiments have confirmed that rapid global processing of object dis­plays does exist.¹⁰

Potential Initiatives: Designing a complex combat sys­tem is difficult. A unique opportunity exists now because the explosion in computing technology and applications is in full swing when the newest combat systems are in de­velopment. If computing capacity is no longer a problem, then the problem may become strictly software. Macro assemblers, or macros, might be used to exorcise the la­tent, or blatent, hostilities in “user-friendly” systems. Commercial vendors include macros in generic applica­tions so the customer can tailor the software to his specific needs. They work like the redial button on a pushbutton phone. You show the system what you want it to do by operation, not by programming, and it remembers that sequence of operations. Macros can streamline cumber­some interfaces, recoup capabilities lost in the design process, provide for additional capabilities, and allow for different levels of user expertise.

In the past, human factors professionals have been hired to fulfill contractual requirements, and the engineers tended to ignore them. Contractors need only meet specifi­cations and get an obliging admiral to like their design in

order to get paid. We cannot continue to ignore how th⁶ user interacts with a combat system.

Objectively better displays in combat systems will pj⁰' vide more effective operation, full use of system capabil¹' ties, and reduce training and software management costs- Today, the price of combined people and associated train^­ing requirements is estimated at close to 60% of the li*^e cycle costs of a weapons system.¹¹ Both DoD and contra^' tors estimate human errors account for at least 50% of ^ failures of major systems.¹² Prototypes fielded with th^e expectation of software updates will probably be ^un' funded, and the fleet will be left holding the bag.

Proponents insist that today’s nagging problems in p^r° curement are developmental snags that will disapp^eaf’ Since the cost benefits of human factors engineering a^{re s}° difficult to quantify, there is little incentive to alter procurement equilibrium. Hopefully, we will not have t° look to foreign navies for extensive man-machine desigⁿ and testing programs.

Human factors engineering seeks to incorporate ^ understanding of man’s capabilities in the design pr°^ce*^s and in doing so objectively derive the most from techno ogy, new or otherwise. The methods exist for accompl^|Stl ing this—if we choose to use them.

'James Kitfield, “How Survivable Are Today’s Ships?” Military Logistics 3(6), March 1987, p. 24.       . _of

²Andrew P. Sage, “Behavioral and Organizational Considerations in the D^cs'£ⁿ,.£ Information Systems and Processes for Planning and Decision Support,” ¹ Transactions on Systems, Man, and Cybernetics, SMC-11(9), September 1981, P 647-648.                                           _d

³General Accounting Office, “Effectiveness of U. S. Forces Can Be l^ncr<j^aj7, Through Improved Weapon System Design,” Report to the Congress PSAD-8 29 January 1981, p. 10.  gjo

⁴William L. Bewley, et al., “Human Factors Testing in the Design of Xerox s ‘Star’ Office Workstation,” in CHI-83: Proceedings of the Conference on Factors in Computer Systems (New York: Association for Computing Ma^c^^,n 1983), p. 77.                                                  _ei.

⁵William P. Marshak, et al., “Situational Awareness in Map Displays,” , ings of the HFS 31st Annual Meeting (Santa Monica, CA: Human Factors Sod 1987), p. 535.  _sal.

Harry L. Snyder, “Counterintuitive Criteria for Visual Displays,” in ^U- vendy, S. L. Sauter, and J. J. Hurrell, Jr., eds., Social, Ergonomic and ^ Aspects of Work with Computers (Amsterdam: Elsevier Science Publishers, I p. 151, 155.                                                                      ._fle

⁷S. M. Luria, Joseph DiVita, and Lt. David F. Neri, USN, “Improving Subm^a Sonar Displays,” Naval Institute Proceedings, February 1988, p. 100.

⁸Sidney L. Smith and Jane N. Mosier, Guidelines for Designing User l^nter Software, Technical Report MTR-10090/ESD-TR-86-278 (Bedford, MA- MITRE Corp., August 1986), DTIC Report AD-A177 198.                                                                                                              f,

⁹J. W. Gebhard, “Visual Display of Complex Information,” Supplement ^ Survey Report on Human Factors in Undersea Warfare (Washington, D-C* ^9 tional Academy of Sciences-National Research Council, 1954), Prepared in by the Panel on Psychology and Physiology Committee on Undersea Warfare 39-61.

^l0Robert C. Munson and Richard L. Horst, “Evidence for Global Process¹ Complex Visual Displays,” Proceedings of the HFS 31st Annual Meeting ( Monica, CA: Human Factors Society, 1987), p. 780.

“George N. Graine, “The Engineering Syndrome vs. the Manpower, P^erS ^5. and Training Dilemma,” Naval Engineers Journal, 100(2), March 1988, P- ' ¹²GAO, p. 27.

Mr. Urban is currently a researcher at the Naval Ocean Systems San Diego. He completed two tours of duty as Tactical Training ment Director at the Submarine Training Facility, San Diego. Mr. . served in various division officer assignments on the USS Plunger w 595) and as navigator/operations officer on the USS Permit (SSN'** ,_s He graduated from the Naval Academy in 1975 and received a m»^s degree in nuclear engineering from the University of Virginia.