Chapter 33: Redundant Trade-offs

Old Jia sat at the end of the long conference table, listening to the discussion with his brow slightly furrowed. One hand gripped a thermal mug, while the fingers of the other tapped rhythmically against the table, betraying a sense of unease.

"If we install these reclining chairs on the aircraft, how much fuel can we carry?" Old Jia finally spoke, his voice steady and resonant.

Planner Lin Yueshi responded immediately, her tone clear and confident: "Teacher Jia, the distance from Jiangcheng to Zhuao is 1,200 kilometers, so we only need about one-third of a full tank. We have two-thirds of our payload capacity remaining, so installing a few reclining chairs is no problem. The aircraft’s weight capacity is two tons; we plan to load one ton of fuel, leaving another ton of buffer for cargo. One ton of fuel can carry us 2,000 kilometers, which is more than enough for the trip to Zhuao."

Old Jia listened, seemingly on the verge of speaking but holding back. His silence felt like contemplation, or perhaps anticipation.

Dr. Yu Ying noticed his hesitation and said, "General Manager Jia, please speak your mind. You have a wealth of experience, and we would value your insights on this plan."

Old Jia looked around at everyone, paused for a moment, and said solemnly, "My suggestion is this: do not install the reclining chairs. Fill the fuel tank to capacity and perform this long-distance ferry flight at maximum fuel and maximum load. This will be a true test for the aircraft. Unforeseen circumstances may arise during the flight, and having a full tank always provides peace of mind."

Feeling a bit parched, Old Jia picked up his thermal mug for a sip of tea, but finding it empty, he merely drained the dregs before continuing earnestly. "Perhaps it’s because I’m getting older; old folks tend to worry more. For instance, before I take a car out on the highway, no matter how long the journey, I always make sure the tank is full before I get on the road. With a full tank, I don’t panic if I hit traffic jams or icy roads; I can use the air conditioning without worry. It’s not like you youngsters nowadays who love electric vehicles. You get on the highway and worry about not finding a charger ahead, so you don't even dare turn on the AC. It’s sweltering in the summer and the battery drains rapidly in the winter—isn't that right?"

Old Jia tilted his head to look at the young people. Seeing them listening silently without a word, he smiled. "Heh, those of us driving gas cars are the old-timers now. It’s not as fashionable or 'sci-fi' as an EV, so almost all of you youngsters drive electric. What does it feel like? Do you have range anxiety?"

"Driving an EV on the highway is terrifying—you’re afraid of running out of power, and even more afraid of the queues at charging stations," the room erupted in a buzz of chatter.

"Ugh, last winter break, my dad drove his fancy TSL to take me to the airport, and the battery percentage dropped like the stock market—plummeting into an abyss," system operator Chen Shihan complained with a frown, clearly still haunted by the experience.

"Exactly! Especially when you see that percentage dropping like it's in a race, and there's a long queue for the chargers at the service station ahead. I’ve honestly wanted to just abandon the car and run," payload officer Zhao Siqi said, leaning back in her chair with a hint of a Cantonese accent. "On the highway, you don’t dare use the AC in summer or the heater in winter for fear you won't make it to the next station. That’s not driving—you’re being driven by the car!" Her comment was so amusing that it set off a round of laughter.

Lin Yueshi saw how vividly everyone felt about this and acknowledged the logic. However, as the planner, her goal was to find the optimal solution by considering all factors. She jotted something down in her notebook, looked up, and said, "Everyone’s concerns are valid, but carrying a full load of fuel is extremely inefficient. It's like an EV dragging a massive pile of batteries around—the batteries weigh more than the people and cargo combined. Generally, from the perspective of economic airworthiness, transport aircraft don't need to be filled to capacity. We should plan a reasonable redundancy based on the flight range."

The room fell silent again. Old Jia thought for a moment and continued, "Intuitively, safety redundancy seems to conflict with economic efficiency. But within a complete system, a certain degree of redundancy ensures stability and reliability, reducing the probability of system failure due to errors or accidents, thereby improving efficiency. However, 'too much is as bad as too little.' A blind pursuit of stability through excessive redundancy will eventually erode efficiency. In practice, we always seek a balance between safety redundancy and economic efficiency. From the perspective of economic airworthiness, Lin Yueshi’s plan for one ton of fuel is a highly efficient amount that ensures standard safety margins.

"However, this is our first public appearance. We cannot foresee every risk, and we cannot afford to fail. If we fail, it would be a catastrophic blow to this drone project. Therefore, we must prioritize safety above all else. We must ensure a successful landing and use this long-duration flight opportunity to fully test the performance boundaries of the aircraft. For this trip, I believe we should ignore economic costs and spare no expense to ensure safety. Within our capabilities, we should implement every safety measure possible and maximize our safety redundancy to ensure nothing goes wrong. In research and industry, just as in finance, we must have a 'bottom-line' mindset. The risks we cannot bear are our bottom line."

The group fell silent again, with some whispering to one another.

Cui Yinuo stopped the side discussions and spoke first: "I agree with Teacher Jia. This exhibition is our first; we can only succeed. We must ensure a victory with zero margin for error. Treating safety redundancy as our highest operational standard should be our only consideration. As for economic costs, we can save on accommodation expenses—it’s just the cost of a ton of fuel, isn't it? Spending money on safety is never a loss!"

"Exactly! Aviation kerosene only costs 6,000 yuan per ton, while hotels in Zhuao are around 800 yuan a night. A ton of fuel is worth at most eight hotel rooms. With so many of us going, we can rotate between two rented apartments and sleep on the floor; the savings will be more than enough to cover the extra fuel," Long Wuyang added enthusiastically.

"Hey, you two are getting awfully in sync, aren't you? Finishing each other's sentences!" safety officer Zhou Mengyao teased, drawing another round of laughter. "But from a safety perspective, I also strongly agree with Teacher Jia."

"Yes, we all agree with Teacher Jia's suggestion!" the group chorused.

"Very well, since everyone is in agreement, it is decided," Dr. Yu Ying said, making the executive decision. "Long Wuyang, you are responsible for fueling the plane tomorrow morning. We depart at noon. The four students on the Zhuao support team will handle the arrival. Once the aircraft has landed safely, the students in Jiangcheng will head to Zhuao in two batches. Please submit the lists to Li Xin Yia. Now, let the other groups report their preparations."

At this point, Master Wang spoke up, addressing Long Wuyang: "Don't fuel too early tomorrow morning. If you're departing at 12:00, refuel at 11:00. It's winter in Jiangcheng, and the temperature difference between morning and night is too great. Refueling when the temperature rises at noon means there will be less air and fewer bubbles in the kerosene, resulting in higher fuel quality."

"Understood, Master Wang. I've learned another trick from you," Long Wuyang replied happily.

"I’ll report on the preparations for the diversion airfields along the route," navigator Zhou Zixuan began. "We have identified three general aviation airports as emergency diversion points. The emergency response team members departed yesterday and have arrived at all three locations. Coordination with the local airports is complete."

Communicator Sun Mengjie raised her hand: "The inspection of the multi-frequency radio communication link system is finished. We have also adopted 5G and satellite communication systems as backups; the anti-interference system has been upgraded and reinforced, and everything will be ready for use tomorrow."

The meeting lasted until past ten in the evening. They reviewed potential issues and contingency plans one last time, ensuring everyone felt confident and prepared.

"Well, practically all necessary measures are in place," Dr. Yu Ying concluded. "Tomorrow morning, everyone will perform one final pre-flight inspection of the entire system. We have plenty of time. Get some rest, everyone. Meeting adjourned."

The night was deep, but the industrial park remained bright. As Old Jia caught a ride back to the Yu Garden, he watched Dr. Yu Ying and the students walking back to their apartments in small groups. Their shadows swayed under the lights. Seeing everyone dedicating themselves to the final preparations for tomorrow's flight, Old Jia’s heart was filled with boundless anticipation.