First flight - Flight profile

[rzbill]

My thoughts were stirred by Flyguytkis experience with the stuttering engine.
It made me search the forum for discussions about the nitty gritty of planning a first flight. I remember a few short threads but not really what I was looking for.

So.. I want to share with others what I did, for consideration. Constructive discussion is welcome.

The flight profile I used is more applicable to longer runways such as KAVL
My gut says 3000 ft or longer to make this useful in any way.

To start:
Briskly in with the throttle to give opportunity to confirm full rpm.
Break ground
Climb a little (20 -30 feet)
LEVEL OFF
Build speed, glance at oil pressure and CHT.
At the point where I could no longer land on the runway, I smoothly pulled into a right hand zoom climb that ended at pattern altitude with my craft oriented parallel at the end of the runway on downwind ready to turn and land if necessary.
Again, glance at oil pressure and cht
Continued climbing and circled the airport in a left hand rectangle to keep myself in a gliding position as much as possible.
Circled a few times and came in to land.


There is a percieved advantage to this zoom climb method in that the intent is to maximise the useful time/length of the runway (by not climbing far from it in the beginning) and also to minimize the residence time in the impossible turn zone.

Merely as an example for discussion, I apply what happened to Flyguytki to the profile above.

1) There was one cylinder reading out of whack pretty early. Enough so that an immediate abort might be possible depending on the length of the runway. The 8K at KAVL would have given plenty of time.

2) The power loss appeared at about the time my zoom would have been finished and I would have been in downwind position ready to turn and land.

SO, in my case, I would have been in a good position but my only course of action would have been to complete an immediate downwind landing.

This pattern was suggested to me by a very good friend and highly experenced military pilot and homebuilder a number of weeks before I flew. I considered it at length and decided I liked it. I still do after doing it.

Gents, let the discussion begin. I hope this can be useful and safe for some other first flight in the future.

 

[pierre smith]

Yep

Bill, I've practiced and recommended a similar first flight profile if there's only one runway. I start a turn to a 30 degree angle away from the runway toward a sort of downwind leg and have practiced turnbacks...(but that's a discussion that was beaten to death).

If there are multiple runways, you're much better off. I had an opportunity to do a first flight with a -7A at a South Carolina airport that was basically a triangle. You could land the airplane from anywhere during the circling overhead.

The worst scenario is a single runway with houses and buildings all around it, such as Mc Collum, in northwest Atlanta, where I did a -10 first flight. I was not a happy camper, with one east-west runway.

I much rather prefer a smaller country type airport with open fields than a city type of environment.

Best,

 

[rzbill]

Bill, I've practiced and recommended a similar first flight profile if there's only one runway.

You are right about the single runway criteria for what I posted. Thanks for pointing it out. Multiple runway availability changes the whole game so the profile would be different.

 

[Andy Hill]

You are right to consider all the above, but I'll add some balance

A genuine first flight will be new for the airframe, often new for the engine, certainly new for the engine installation. So I am suggesting do not concentrate on the engine "problems" exclusively - a 20' to 30' level off is pretty non-standard on any day - for the first flight of an aircraft quite a step?

What actually does it achieve? You are now gaining KE rather than PE, but if either the engine, or you, decide to land back on, total energy will be similar so the landing outcome little changed?

I would concentrate on a shallow climb to achieve high IAS quickly for CHT reasons, minimising control inputs. I do the 1st takeoff flapless if circumstances permit to minimise issues there. I do some form of climbing turn as you describe to maximise gliding opportunities. I have heard it said if an engine is to fail on you, it often does at power reduction, so I will not touch anything until well in the overhead.

There was one cylinder reading out of whack pretty early .... but my only course of action would have been to complete an immediate downwind landing

As you say, a risky option - if the engine is really poorly performing that might be the best choice? But I would not do it based on 1 "indication" - I have had few engine issues in testing, but plenty of indication problems

In the UK we have suggested flight aims for 1st flight:

1. Solo (i.e. no observer) 15-20mins
2. Ensure basically flies OK
3. Ensure Engine does not overheat
4. Satisfy yourself aircraft is fit to leave the circuit
5. Post Flight, pull cowlings and look closely

We have at some point to achieve a 2hour flight, so I often do that next, with the owner as observer, getting readings and doing the bulk of the "break-in".

1 lesson I have learned with Injected engines is to note carefully the EGTs at full rich at, say, 1200RPM. Now lean quite a lot, and take EGTs again. Now compare the rises across the cylinders. This should (and did for me albeit later than ideal) reveal an injector issue prior even going flying.

I doubt there is a perfect profile - there will be a wide range of opinions and aims. But as you do, think things through, and follow the plan

PS and above all keep it low key. Do not announce it, do not get everybody round, avoid a crowd. Have a clear decision point just prior takeoff where you say "is everything really looking correct"? Not just "it should be OK".

 

[rzbill]

Thanks for the counterpoint Andy.

In regards to the nonstandard action of leveling off, I found it to be quite easy and controllable. I'm not sure that I could claim any additional risk in it.

I understand your point about trading KE for PE, but I think the pure trade would be in a vacuum instead of the entropy raising world of the atmosphere. I did some calculations to try to make a comparison. I won't go into the details because they are a bit tedious for e-mail (and I might get smacked by the likes of Steve Smith ) but I think the energy dissipation paths to land at end of same runway are different enough to give a slight edge to the leveling off technique. To your point, it is a closer race than I thought it would be. In my case, if my assumptions and calcs were appropriate, I gained the use of about 500 feet of runway by leveling off. This would be shorter for shorter runways.

Interesting tip about the EGT test. I'll use it when helping other builders.

 

[N941WR]

One tip that Ken K. (formally with Van's) mentioned that he did prior to a test flight was to "fly" the profile on Google Earth.

That gave him the ability to pick out potential landing sites, just in case.

It will also allow you to pick a flight path that avoids towers, schools, old age homes, etc.

Smart man, that Ken.