Mid-runway departure?
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bbchien
Touchdown! Greaser!
In a light twin it's a matter of discipline. Unfortunately the record shows, that for GA, a lot of guys don't have it.
PilotAlan
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PilotAlan
When in doubt, climb. No one has ever collided with the sky.
skidoo
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Sometimes yes, sometimes no - PIC makes the judgment call.
i.e. 182 at max gross 3100 lbs at takeoff, but less than full fuel. Or, need to immediately return and land after takeoff at max gross, but now over max landing weight (2950 lbs). The extra fuel not on the ground in that case can be detrimental.
How about less turbulence, or greater visibility?
How about with a 25kt headwind, one takes off at mid field, climbs to 1000 ft, engine quits, turn around and now that runway that was behind you now provides more in front of you...
TMetzinger
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No argument in a light piston twin.
Everskyward
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There are lots of time that leaving fuel on the ground is a good idea.
Ted
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iFlyNothing
Yet I've seen you fly out of Gaston's, significantly less than 4700 ft (much less 11,000).
I agree, but the discipline is in the procedure more than anything, not saying "requesting full length." As with the rest of flying in twins, the extra engine is useless if you don't know what to do with it, or if the performance is so lackluster on one engine that you're going down anyway.
The 310 was based out of a 2900 ft strip for the 25 years prior to me starting to fly it. You bet that required discipline and some good piloting to get it in and out of there- that's a tight strip for a 310, especially at gross on a hot day (the Colemill conversion ad VGs do help). In 25 years and 3000 hours of flight time, it didn't have any incidents. No, it also didn't have any engine failures on takeoff (did have one in cruise), but the procedure associated with getting the plane in and out of 2700 ft safely (and being prepped for the engine failure at every possible moment) also helped with that. I don't know your Seneca's performance and I suspect that if I was flying a Seneca rather than an Aztec or 310, I'd have lower tolerance for reducing runway, but the answer is highly variable.
I won't fault anyone for taking the extra runway, but faulting others for choosing not to take it when a normal takeoff can be performed is silly.
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Ted
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You prep for the engine failure in a twin. Whether you're at an 11,000 ft strip or a 3,000 ft strip, your procedure should be no different for being able to handle the engine failure. You'd also be surprised how much runway it actually takes to stop a twin at V1. Sometimes that may be a better option, but if you've gotten to V1 already, you've got a lot of kinetic energy for those little brakes to dissipate. Try it and see how much runway you eat up.
Flying out of Sky Manor (2900 ft with obstacles) in the Aztec or 310, if the gear is up, I'm going, feathering the bad engine and Vxse until over the tree tops. There's no way I'm going to stop before those trees if I'm at V1 already. In fact, there's probably no way I'm going to stop before those trees well below V1.
dennyleeb
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7DeltaBravo
by sky above you I mean the higher the better, for example if you were up there you would be better unlike down low with all the sky above you
dennyleeb
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7DeltaBravo
It is more of of don't cut it close phrase. Most all of us know someone who has died b/c fuel starvation. How many do you know who died b/c they had to much. I will get rid of people before fuel...
Ted
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iFlyNothing
Yet most IFR pilots will still happily cruise along at 4,000 ft even if they could cruise along at 15,000 ft (assume unpressurized piston aircraft). At 15,000 ft you have more altitude. You also need oxygen, you may or may not have the power to be up there comfortably, your engine(s) may not be as happy, you end up with headwinds...
Lots of reasons why flying low may make sense.
dennyleeb
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7DeltaBravo
On the last one you are joking right? You know you don't have to turn the first second the engine quits right?
kevin7500
Pre-takeoff checklist
Shouldn't it really be a couple guys talking about how the Seneca lost power in the left side on take off, Mayday'd the tower, entered the pattern and landed without incident? I thought Seneca's would still climb with one engine....really slowly. Is there a reason to try to force it back to the ground rather than fly around and land is a controlled way?
Ted
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That depends on the situation. If you have the runway or know you can't clear the obstacles, I do agree with Bruce that the safe thing to do is land straight ahead regardless of what you're flying.
The decision point is gear up. You hit V1, establish a positive rate of climb, get to the point where you're out of usable runway, and pull the gear up. At that point you're committed to going. Establish Vyse or greater as quickly as possible, and have your identification method down solid. You have a very limited period of time with which to feather the dead engine (which is not instantaneous) and get rid of that drag.
Bruce is correct that most twin pilots don't have the discipline to be religious about engine out procedures, especially on takeoff. The question you need to ask yourself is, for every point on the takeoff, "What do I do if my engine fails here?" That needs to be answered before you take the runway.
Aztec Driver
Line Up and Wait
I agree Ted.
Bruce,
We've also seen you take off out of Windwood, at around 3000 feet, and tall obstacles all around, and higher density altitude than this field.
You are right, it takes discipline to fly a light twin and be prepared to initiate proper procedures. It also takes discipline to fly a single. You still need to be prepared. I normally fly out of a 2400 ft strip, and yes, it takes a little planning. If I plan on a gross weight takeoff on a hot day, I will usually take the passengers to LNS for a better runway, but I CAN make it out of S37 if I need to. To say that 4500 feet is not enough, and then to fly out of 3000 foot strips is hypocritical. The same due diligence is required, why the difference in choice?
I won't deny the decrease in safety factor in choosing to use less runway, but if that is your sole motivation, then you should not land at runways that are less than your prescribed safety margins. Set your personal minimums and stand by them. If you choose to lower your minimums, make sure you have the procedures in place to minimize risk in the event something goes wrong.
I base my takeoff requirements on the expected performance of the aircraft in the current conditions, as I know you do too. 4500 feet is quite a bit longer than accelerate-stop distance in this aircraft, even at max gross. While there is certainly a higher safety margin with the full 11,500 feet, I see no reason a normal takeoff can't be accomplished with an adequate safety margin.
Can you explain your rationale on this? I know you fly out of reasonably short strips fairly often, and you may adjust your weight accordingly, but you still would not have the safety margin you would have at the intersection takeoff at this field.
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kevin7500
Pre-takeoff checklist
Missa
En-Route
First time I flew into KOSC I decided I would go to the end of the runway. That is a decision I will not make again.
flyingcheesehead
Touchdown! Greaser!
Not Bruce, but he's usually WELL under gross in his Seneca on those short fields... Unless he's got me aboard. 
flyingcheesehead
Touchdown! Greaser!
If you're low enough, you either start the turn NOW or you don't make the turn at all.
tonycondon
Gastons CRO (Chief Dinner Reservation Officer)
i find it interesting that after doing a lot of glider flying, in which you can pretty safely usually execute a turn back when above 200 AGL, i still find that my best overall option is still to land straight ahead in the field off the end of the runway rather than try to get back to the runway for a downwind landing.
dmccormack
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Dan Mc
At some large fields, it can take so long to taxi to the end of the runway that you risk overheating, especially if there are lots of intersections.
Get me to the closest intersection and let me go. If I'm that concerned about 2000' behind me on a 6000' runway, maybe I shouldn't fly this airplane at this field.
Get me to the closest intersection and let me go. If I'm that concerned about 2000' behind me on a 6000' runway, maybe I shouldn't fly this airplane at this field.
Fearless Tower
Touchdown! Greaser!
Exactly - take my example of the Champ starting taxi from the opposite end of an 8000' runway - unless you are planning to do 3 or 4 takeoffs and landings in the same run, there is nothing really gained by using full length there.At some large fields, it can take so long to taxi to the end of the runway that you risk overheating, especially if there are lots of intersections.
Get me to the closest intersection and let me go. If I'm that concerned about 2000' behind me on a 6000' runway, maybe I shouldn't fly this airplane at this field.
Fearless Tower
Touchdown! Greaser!
Here's another good example of when you should take an intersection departure - GA taking off 25L at PHX
http://204.108.4.16/d-tpp/1104/00322AD.PDF
Unless you are in a heavy jet, tower will give you the intersection departure at H7. If you really want the full length, you have to wait to be cleared across the runway and then continue taxi down to the end which really isn't much further. Absolutely no point in a light GA aircraft. Even in a twin, I have a balanced field taking off from H7.
http://204.108.4.16/d-tpp/1104/00322AD.PDF
Unless you are in a heavy jet, tower will give you the intersection departure at H7. If you really want the full length, you have to wait to be cleared across the runway and then continue taxi down to the end which really isn't much further. Absolutely no point in a light GA aircraft. Even in a twin, I have a balanced field taking off from H7.
wabower
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Wayne
My souped-up airplane needs a few hundred feet, but I use the entire runway on every takeoff because the environment surrounding the home airport isn't conducive to off-field landing. By using all of the runway I can either land and stop or achieve sufficient altitude to circle and land on the take-off runway.
Bottom line is that whatever runway length is available is what I'll use at any airport no matter which airplane I'm flying at the time, primarily to lessen the impact of an aborted takeoff. Having heard about many oopsies that occur at lift-off or shortly after (and seen a few first-hand) I know it's much easier to just land and close the improperly latched door than to fly a pattern with paperwork being sucked out. If the oil hasn't warmed sufficiently, or if I'm still working on pre-departure stuff, the extra taxi time is of no consequence anyway.
Bottom line is that whatever runway length is available is what I'll use at any airport no matter which airplane I'm flying at the time, primarily to lessen the impact of an aborted takeoff. Having heard about many oopsies that occur at lift-off or shortly after (and seen a few first-hand) I know it's much easier to just land and close the improperly latched door than to fly a pattern with paperwork being sucked out. If the oil hasn't warmed sufficiently, or if I'm still working on pre-departure stuff, the extra taxi time is of no consequence anyway.
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bbchien
Touchdown! Greaser!
That's a different number, Kevin, the Accelerate Go number which does not exist for part 23 aircraft. In part 23 we assume that it is Vyse, whcih on a full gross day would give me 90 knots at +230 feet per minute, if I did everything perfectly. If I haven't made Vyse when I have the engine out, no way will it climb away, unless it's WAYYYY below gross.
Condition #1:
V1 speed (VARIES with weight and dALT, Wind and temp and baro): the speed to which I can accelerate, hesitate 3 seconds, and stop and not quite hit the fence) may be above, below or at Vyse. If it is below Vyse (VARIES WITH WEIGHT), I have committed to a takeoff out of which I cannot climb out or nor stop before the fence. BRYWD, that is okay, but I don't do that if I have another choice, and I'll only do that if my passengers are all pilots and agree to the small but never zero chance of something going wrong. More recently this has been reduced to those who will benefit from my estate, mostly (SOME Gaston's exceptions, granted).
Condition #2:
If V1 speed for the day = Vyse, then I will accept the departure and fight it out in the air or on the ground depending on the condition.
Condition #3
If V1 speed is is >Vyse, it's not a fight. It's shut down, and get out of a perfectly undamaged aircraft (maybe a flat tire). CAR 25 aircraft have another speed, called the "safety decision speed" and it's above V1 speed. This is essentially the max speed that the pilot can get it stopped without a fire or other disasterous consequence, and after that speed he is committed to manage the emergency as if it were an inflight emergency.
So, why would I accept any departure in the First condition, when with a little back taxi, or a little ground departure wait, I can make it into condition 2 or condition 3? That's just silliness. BTW the FAA thinks so too.
Remember who was in the plane with me? She would benefit from my estate anyway. So there I have the option to accept condition #1 at Windwood, Gaston's AND and 6Y9. And a 400 hp cherokee, light, is a VERY capable shortfield aircraft, even though I need 80 mph to execute the procedure. I simply have to accept the trees if I lose one.Aztec driver said:
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Ted
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iFlyNothing
While your logic does make good sense, Bruce, I don't see it as a rationale for why people perfectly willing to take off from a shorter runway assuming conditions 2 or 3 should feel obligated take a full runway, when the intersection departure provides greater than ample room for it.
"I prefer it," however, makes perfect sense.
What you describe in condition #1 is more along the lines of having a situation where you have several seconds for which an accident will occur if an engine fails. That is definitely to be avoided. In that case, I fully agree that the pilot needs more runway if it is available.
"I prefer it," however, makes perfect sense.
What you describe in condition #1 is more along the lines of having a situation where you have several seconds for which an accident will occur if an engine fails. That is definitely to be avoided. In that case, I fully agree that the pilot needs more runway if it is available.
bbchien
Touchdown! Greaser!
My V1 at 500 MSL on most summer days, finally equals Vyse at 4,700 feet. That should mean something to you, think about it.
When I could have condition 2, or 3 by taxi-ing back....see 4,000 is not enough to close the vulnerability window. I need 4,700 at my typical loads, no wind, 29.92 and a level runway.
In the example being discussed, the intersection departure leaves with just 4,000. WHY whould I accept that when thousands more are for the asking? Or even 700 more is for the taking?
Ted, do one more rating. You need to think like an ATP.
When I could have condition 2, or 3 by taxi-ing back....see 4,000 is not enough to close the vulnerability window. I need 4,700 at my typical loads, no wind, 29.92 and a level runway.
In the example being discussed, the intersection departure leaves with just 4,000. WHY whould I accept that when thousands more are for the asking? Or even 700 more is for the taking?
Ted, do one more rating. You need to think like an ATP.
Ted
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iFlyNothing
If you read my post, I agreed with you on that point. So if that's your only gripe, what are we arguing about?
The topic drifted to the 11,000 ft runway with 5,000 available. Perhaps that was where the confusion set in.
Double edit: Now I re-read, and realize I misread that second situation, it was actually 4,000 available with the 11,000 ft runway. In the 310 with 600 hp, that's easy even with full load on a hot day. The Aztec it depends on loading and the weather. I'd probably want more runway if I had passengers or a heavy load and it was hot. If it was lightly loaded (especially if cold), it'd be different. That said, it still takes off at close to gross on <3500 ft strips just fine, but there is the risk assocaited with that (just like with waking up in the morning). In the places I go where that's done, that's also routine procedure - the DHC-8s and 1900s use those same runways loaded with passengers and cargo.
Sorry, on that point I was confused about the situations.
If that's your definition, I already do. But that's in the works anyway...
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denverpilot
Tied Down
I heartily believe one *should* brief and prep an engine failure at takeoff in singles too.
I'm always a bit appalled when someone can't tell me their "plan".
Had two CFIs who required briefings and or at least a discussion about where the aircraft was going to go if the engine quit below 500' AGL (move up or down as necessary for all conditions) and above. Accounting for wind, known obstacles, calculated or known aircraft performance numbers, etc.
It's Airmanship. Know the plan, fly the plan. Don't be tempted into doing something that is higher-risk or even guaranteed to kill you. (The "Impossible Turn"...etc.)
Fearless Tower
Touchdown! Greaser!
Exactly - a proper departure briefing should be the norm regardless of how many engines you have on the airframe.
PilotAlan
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I agree.
But in the absence of mitigating factors, I fly the highest altitude available.
I flew back from KOSH two years ago and never got above 2k feet due to howling headwinds higher than that.
The year before, winds weren't a significant factor. I flew back as 12,500.
My last trip back from Virginia I varied from 12,500 to 3,500, depending on conditions. But it was always the highest practical altitude.
Runway length is the same. I will take the greatest practical runway length available. If there's a bunch of jets holding at EOR, then OK, give me the intersection.
If it's a 15,000 foot runway, OK I'll take off at the intersection with 10,000 (or 8000) remaining.
But saying "I have to taxi all the way to the other end" seems like get-there-itis to me.
I have to make these decisions all the time. At home, to get to Runway 35 when the winds are cranking from the north is a 4 mile taxi. It's tempting to take off on the east-west runway regardless of winds, because it's a 1/2 mile taxi. But that's taking the easy way solely for convenience, and it's going to bite one day. So I taxi to 35.
Again, it only has to make a difference once.
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Everskyward
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There's a big difference between cutting it close and the old "you can't have too much fuel" statement.
There have been many accidents which could have been avoided if the airplane was lighter, and one of the ways to make it lighter is to carry less fuel. Carrying less fuel is at least as good an option as kicking someone off the boat. You just can't fly as far.
Everskyward
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Capt. Geoffrey Thorpe
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Light and Sporty Guy
I thought about this thread this morning when tower asked us, "Can you depart from Foxtrot or do you need the full length?"
In case you are curious we departed from Foxtrot.
I would have taxied at least as far as Bravo 3 before departing on 07.
But for the original scenerio, the intersection in question would give me enough length that by the time I ran out of room to abort, I would be more than high enough to turn back.
Fearless Tower
Touchdown! Greaser!
I thought about this thread this morning when tower asked us, "Can you depart from Foxtrot or do you need the full length?"
In case you are curious we departed from Foxtrot.
OMG - you left USABLE runway behind you!!!!
Ahhhhhh what a world what a world.........
dennyleeb
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7DeltaBravo
Well I am a "IFR" pilot and I prefer it high in my turbo w/ o2. Having said that you throw up a random number 15k which is beyond the limits of some planes. It is different for diff. planes and situations of course. I guess I should have explained if there is a 100kt headwind at 10k ft and you have a cub it would probably be better a little lower.
Richard
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Ack...city life
I just saw this thread and I don't feel like reading 4 pages of responses so what I have to say may have already been said...
...while talk of RWY length and TO distance is fine...what's not being said is what if you have pax? If it's just me and a pilot rated pax or two...no matter the loading, I may request the intersection departure. Yet if I have pax who either are paying and/or not familiar with flying in small planes, I'm using the full length. Their comfort supercedes my convenience.
...while talk of RWY length and TO distance is fine...what's not being said is what if you have pax? If it's just me and a pilot rated pax or two...no matter the loading, I may request the intersection departure. Yet if I have pax who either are paying and/or not familiar with flying in small planes, I'm using the full length. Their comfort supercedes my convenience.
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Fearless Tower
Touchdown! Greaser!
So, you wouldn't takeoff with pax at F in Everskyward's example?
Clark1961
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I thought about this thread this morning when tower asked us, "Can you depart from Foxtrot or do you need the full length?"
In case you are curious we departed from Foxtrot.
Hey, I've bounced off that runway! It was late night and they tolerated a Skyhawk. I was off again before getting out of the touchdown zone lights. Darned annoying those bright lights down the centerline so I offset.