Jerry, Naturally, you should never fly over legal gross weight.
That's in spite of the basic Coupe structure having been certificated at weights up to 1450 lb. with only minor changes (i.e. landing gear orifice, etc.). Are YOU safe to do so? That would depend on your plane, mostly. You mention that a certain load would "put me at 500 lbs and I know that is over weight" but you didn't tell us critical information. My Coupe, for example, would have had a useful load of 495 lb., legally, had it legally been legally flown as a 415-D. What is the model of your Coupe? (i.e. what is the legal gross weight? If it's a 415-C or 415-CD, do you have the 1320 lb. gross weight STC?) What is your engine? (C-75, C-85, C-90?) What is your prop type, length and pitch? (And, is it really the pitch you think it is.) _______________________ Flying a 415-D (allowed gross weight 1400 lb.), I had a C-85 engine. My prop was a metal McCauley 1B90 with length of 71" and pitch set to climb, a 46" pitch. With that plane, I was comfortable carrying 1400 lb. in almost any conditions from about any runway. The 7146 pitch propeller on the C-85 gave me comfortable short field operations, but, limited my cruise speed at 2400 rpm to 100.0 mph (give or take a couple of tenths). One of my home runways was grass, 1800' useable, with no obstructions, altitude about 1k'. I was always off the ground by mid-field (except in especially bad conditions, i.e. mud). Another home field had a 2400' asphalt runway but had trees at the end, altitude about 800'. My worst takeoff was at 1400 lb. on a 90°+ day with no wind, from a 2400' grass runway that hadn't been mowed for too long, with zero wind, altitude about 500'. That one had pucker factor. But, I was off the ground, accelerating in low ground effect with enough speed and altitude to clear the 5' farm fence at the end -- that was all by my pre-decided go/no-go point. With my 7146 pitch prop, I could always reach 12,500'. When I flew out west, with gross weight around 1320 lb., at the high airports I never needed more than 1/3rd of the runway, even at a 6,700' high airport. I also did my mountain flying from just before dawn to a last takeoff of 10:30 (too late as the thermals were VERY boisterous over the high desert). The rate of climb stunk when ground level was so dang high. I urge you to keep the weight down unless you change to a climb prop. At no point should "I barely made it off" EVER be a phrase you need to use. The penalty for a mistake on this is death, perhaps fiery, slow, screaming in pain death, as happened to the Ercoupe Owners Club President Jack Harkness many years ago. He was a passenger in a heavy Coupe on a hot afternoon departure. I suppose the doctors had him drugged for the pain for the day and a half or two days before he died of his burns. (The pilot died immediately, I think.) Or, I suppose you could just be paralyzed or something. I only have prop numbers for the C-85. For that engine, 7146 climb prop (what I had and even so, the climb ain't that great) 7148 normal prop (we used to call this the climb prop but we've changed our mind) 7150 cruise prop (used to be called the normal prop) 7152 not recommended except on very light aircraft. If you are flying very light, you might be comfortable calling those prop pitches by their "old" names. If you are flying heavy, my new designations firmly apply. If you are flying heavy, for example, a Coupe with a C-85 and a 7152 pitch prop will have a top speed of around 90 mph and almost no climb. The load is too high and the engine can't spin the coarsely pitched prop up. There's some data and some thoughts. I'd urge you to be cautious. Ed
