photofly wrote:
"Never T/O without the WandB or all the calculation done."
Yes, you need either the W&B ("same as last flight") or the calculation ("first time with 3 people on board, better calculate everything")
Going flying without either of these options is setting a bad example as an instructor.
photofly wrote:
There's no requirement, need, or benefit to "have a W&B". It's just another random piece of paper. We simply need to make sure we are inside the approved envelope.
Agreed.
Although, some schools might have that requirement in their FTU manuals, so then it does become a necessity. No idea if yours does or not. The colleges do I believe (based on rumors, have no hard evidence)
How will a 3 hour student pilot make sure he is inside the approved envelope?
photofly wrote:
The "skill" of "having" a weight and balance isn't something that improves with practice, or something at which experienced pilots are "better", so the number of hours of flight time really isn't relevant. If it's good practice at 2 hours, it should be good practice at 10,000 hours, no?
Of course it improves.
A 200 hour pilot will take his 3 fat friends on a tour. He knows he can not take full fuel from previous calculations. He might redo the calculation to take maximum fuel.
A 40 hour pilot takes his family on a tour for the first time. Up untill that point the W&B was always the same, "because it is very hard to overload a 172". He takes full tanks, because "more fuel is better" and leaves overweight. He notices the plane climbs noticeably slower and makes a mental note to do the full W&B calculation next time. Maybe he will make quite a few mistakes, as he has rarely done one.
photofly wrote:
Maybe you could suggest at how many hours of flight time it's ok not to "have" a weight and balance calculation? Somewhere between 10, and whatever .'s total hours are. But where?
When you are willing to bet your life -and if I am your instructor that you have the capabilities to assess such situation- on the fact that you know the plane and load situation well enough to be sure the plane is within limits.
photofly wrote:
Prove to me that you can do the calculation once or twice, then tell me each time whether we're inside the envelope and how you can be confident about it. ("Because I've checked the numbers and it's impossible to be outside the envelope with you, me, no bags, and anything up to full tanks, in this aircraft". Job done.
How does he check the numbers without doing a calculation? That is exactly what a W&B is. I don't care if a student does it via an online tool, an excel spreadsheet, pen and paper, an app, as long as he thinks about it.
Also note he might be flying a different airplane for the first 5 lessons anyway.
Question: how many W&B calculations does your average PPL student do? Only the first 2 lessons?
photofly wrote:
I understand that you're using the tool of forcing a student to have a perfectly accurate W&B calculation for each flight as a means to teach them not to fly overloaded or out of balance on any flight. I don't think it's the best way, because they won't keep it up, as licenced pilots.
That depends. When they are flying commercially, they will have to do one for every flight, even if it is 12 times the same trip a day. They can copy the paperwork from the previous legs, but it will have to be done.
As a PPL: I hope that during the training they will have ran into situations where the W&B did not turn out as expected and that it will stick with them for the rest of their 'career'. Also, if you do it more, you take down the myth that it is a very hard thing to do that takes a long time. If you practice it, it really doesn't.
Another thing I'd like to mention is that W&B calculations, especially the final result and the graph in the POH are sometimes hard to interpret. The location of the COG / moment changes much more than what a lot of students think. Adding a bag in the rear baggage compartment instead of the co pilot seat can make a huge difference. A lot of students underestimate the difference it can make.
photofly wrote:
Pilots (mostly) aren't stupid.
Not all of them are stupid
photofly wrote:They'll do the sensible thing and acknowledge that if they weren't overweight last time they flew with the same load, they're not overweight this time. Just like . does. And just like I and everyone else does. Might as well teach them that in the first place, and alongside teach them that they times they do need to do a calculation are those times they're not flying the same plane with the same load.
I still am convinced that a PPL student does not have the necessary skills to reliable make that assessment without some form of reference to the numbers or graph (previous flight W&B, manual, scribbles on a napkin, computer programs, anything he likes,... )
When they tell you the plane is good to go like that, just for fun, ask them where on the CoG / moment graph they think they are, and then actually calculate it.
The overweight issue is one thing, the CoG location is much harder to predict.