Airplane Takeoff 101 and Balanced Field Length – Risk Management 101
When you hear the word “balanced” in the context of an airplane take-off, it means that you’ve struck a balance between being able to GO and being able to STOP.
A seasoned pilot will tell you there a few things about their first jet that made it memorable. The strongest imprint will be the skill set built that allowed them to get it airborne when an engine failed at the worst possible time. It happened at the moment where they were rapidly approaching the point of no return.
Should I stay, or should I go?
The definition of “balanced field” is simply that: A balance between your ability to stay or go. If the runway length you have available for your take off roll offers both – enough to stop, or go and get airborne, then it is balanced. You are legal to attempt a take off.
Yet a balanced field length has appropriate cousins in the non-airplane world of business: When starting anything, a business, a take off roll, … make sure you have enough runway in front of you. Recently, I was at a board meeting where the discussion centered around this issue – except it was cash needed to get a start up to what venture capitalists refer to as “escape velocity.” The conclusion, after looking at what was being metaphorically pushed down the runway, was that more runway was needed – to be sure, to be safe. Cash, power, thrust, and horizontal distance to give you more time to take flight is what flying jets and business is all about.
When it comes to airplanes vs. business, however, there is no grey area . The right amount of runway keeps the airplane in one piece and potentially saves your life. Lesser beings of smaller airplanes might say things like “oh I’ve heard jets are easier to fly.” Look calmly over your glasses and say: “No son… that’s actually wrong – jet flying requires serious commitments.”
You respond this way because the memory of your first simulator experience is fairly potent – since this is where “Balanced Field Length” was first pounded into your mind as a something that not only kept you legal, but alive.
But despite such grave talk, the fact is that if you play by the rules, the word emergency is not invoked when your first real or simulated airplane loses thrust from an engine on the take off roll. A calmly led business should operate the same way: “We’ve only got half the cash flow, funding, etc. – but this is no emergency.” If you can still make it on 1/2 the power you thought you had available, then you are a good planner, and you get to calmly take to the skies, albeit on a lower climb profile, but at least you aren’t in a heap in the trees at the end of the runway.
With virtually all jet aircraft there is so much power, that when one of the engines fails, you have plenty of power to continue accelerating to what is called Vr or “Rotation Speed” where the aircraft “rotates” from a horizontal trajectory into the skyward one where safety awaits.
(Interested in your jet’s favorite thing? See V Speeds Are Your Friend.)
A key concept to remember is the basic rule of the balanced field: If you can get airborne you are much safer than trying to manage a heavy and fast aircraft with limited runway left to stop, which is why knowing when you’ve passed the decision point, also known as V1. “Balanced Field Length” (BFL) is all about safety. Calculate what it is, make sure you have enough and you are good to go no matter what might come your way.
The Art of Compromise
But what happens when you can’t safely do it? This happens with airplanes and businesses all the time – you could argue it is the art of the launch – what do you reduce, wait for or append to ensure safety?
Airplanes respond to wind, weight and temperature, primarily, when calculating the required distance. This happens a lot, and you could argue that all commercial flying out of smaller airports in jet aircraft typically requires a compromise of some kind. Carry less fuel, restrict the payload – and in severe cases, wait until the temperature cools down (leave at dawn or dusk – or in the middle of the night). The reality of the modern start up is that you go lean on management by default. You also look for fuel – minimum viable product and revenue, as quickly as possible. No customers? No audience? No consistency in the message? No flight.
The reality of operations in any aircraft is that the crew is actually constantly making compromises to make this number work – and they are doing this in the interests of safety. When a crew doesn’t have to make a compromise, then the airplane is performing at its maximum capability. It has all the fuel and people it can legally take off with and the runway is no factor because there is plenty of it. Just as you know in the world of business – such ideal circumstances are rare – most runways require careful calculation and thought.
The typical day, of the typical jet, throughout the big boy and smaller airports of the world requires constant calculation. To be safe, fuel loads are reduced and even passenger loads are limited in order to make each take off within the tolerances outlined by the manufacturer.
In life and business you’ll have many moments where you really wonder – is there enough runway? For jet pilots, fortunately, there is no ambiguity.