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View Full Version : Calling Grumman AA1C drivers!


flyingkiwi73
5th Mar 2017, 23:15
I'm looking to go into a syndicate with a Grumman Gang! and I test flew the AA1C this weekend. I noticed there is a lot of stuff written about the Lynx just like the Tomahawk which seems to be just fear mongering.


So a few things stuck me.... most flying guides say things like:
At 20 Deg C It won't climb with full fuel and two up: We had full fuel, two guys weighing to total of 200KG and it climbed at 500ft/pm at 80 knots. it was 18degrees 1013mb at MSL ??? The climb was observed by me to be faster than the Tomahawk which I flew 1 hour later. 15 litres MORE fuel but slightly lighter passenger. Climb at 70 kts, 600ft pm slower by a good 30 seconds to 1000 ft.


DON"T TURN FINAL WITHFULL FLAP (caps left in from the post I read) We did at 80 knots (20 knots below max flap speed) didn't die and made a great landing 4 times.


Don't taxi without nose wheel straight: (castoring wheel) ... I pointed this out, the pilot said watch the A/C Moved forward wheel straightened...


Stalls a quick and pronounced: nope, just the same as a Tommie, ok we didn't spin... but I imagine the warnings about that are possibly over blown (I will never spin this AC BTW)


I know there is a of of smack written about the Tommie which is bollocks if you fly it like a pilot and not a moron (doing the same stupid things in a 152 would kill you too) I have 200+ hours in the Tommie and don't recognise the supposed nasty features often espoused


So my question to Grumman drivers,... is this all bollocks or is there a bite waiting for me?? I feel the aircraft has quite a long take off roll and is not short field but as far as I can tell it handles like a Tomahawk.


Please feel free to correct me!!! I genuinely want to know form Grumman folks about operating these lovely aircraft.


Thanks


FK73

India Four Two
6th Mar 2017, 08:04
Kia ora fk73,

Welcome to PPRuNe.

I've only flown the AA-1A and B, for a few hours, many years ago.

They fly perfectly well, provided you stick to the recommendations, concerning flap and speeds. It's not a short-field aircraft and I only flew it on seal (tarmac to non-Kiwis), so I don't know about it's performance on grass.

I've also got several hours in a Tomahawk, which I also enjoyed flying.

I see that the AA-1C has a very similar Vso, within a knot, to the A and C:
"Grumman" Aircraft Specifications (http://grumman.net/cgrcc/specs.html)

So 1.3 x 53 kts Vso = 68 kts or 78 mph, which matches the 80 mph approach speed I was recommended to use. So I think your 80 kts approach speed is a bit fast.

(I will never spin this AC BTW)

Absolutely vital*. Back in the 70s, the CFI of the company I rented from, insisted on demonstrating a spin to a newly-hired instructor, inspite of the prominent NO SPINNING placard. The spin went flat, the CFI was killed and the new instructor was crippled for life.

* unintended pun.

PS Good writeup here: Aviation Consumer - The AGAC AA-1 (http://www.aviationconsumer.com/sample/AGAC-AA-1.html)

VictorGolf
6th Mar 2017, 11:45
I keep my New Zealand built Airtourer 115 on an 800 metre grass strip and I'm in a hangar next to an AA-1 whose owner is very happy with it. Performance seems to be the same as the Airtourer with perhaps a slightly longer take off run for the AA-1. Cruise seems to be about 5 kts faster for the AA-1 but otherwise it's "even stevens". However if you're in NZ I'd go for an Airtourer as AESL/PAC are based there if you need the bits.

flyingkiwi73
6th Mar 2017, 19:03
Thanks guys.
And thanks for the references, some I had not seen!


So I see the ground roll for an AA1C over 50' is around 485m, for the Tomahawk its 445m


So as I left 07 (610m) at Omaka the other day in the Tommie (since you guys seem to be kiwis) I had 27% of the runway left when I rotated, Which seems about right (I keep the nose wheel light and then climb flat until I see 70kts). In a Grumman that would be reduced to 21% of the runway or 125m left of the strip. that's a bit tight, I would possibly have used 12 or 01 and taken the xwind??? Its grass but its well maintained and mown.


At NZPP with 999m to use, the AA1C rotated maybe slightly after the Tomahawk did, climb rate was about the same, but I noticed the guy I was with maintained a 80kts climb rather than the 70 kts I would use in a Tommie. ( I flew both aircraft 1 hour apart so have a good comparison)


So I'm feeling on the ground and in the landing it behaves like a very full and slightly asthmatic Tommie??? I can deal with that.


WB is another thing I know could be a factor.... and may have done but you can't prove it... flown a Tommie over gross weight (long seal runway good headwind). This feels like something you should never do in a Grumman ??? especially anything aft? any comments there?


As for approach the warnings I have seen is don't turn final with full flap, I do this in a Tommie at 70kts all the time no issue. (if you every hear the beep check forward no harm done) I noticed the turn to final was done with full flaps but at 80kts, I asked the guy about this and he said he's never heard about the warning and he turns final with full flap all the time, however I see he was 10kts faster.


The remainder of Final approach was flown at around 70kts, touch down about 65kts, so we weren't screaming in at 80knots. same RPM it seemed to me 1800-1900..... so bolt on a few knots in the circuit for safety, get rid of it on and established final?? I can do that.


I noticed when I was turning - steep turns the airspeed did trickle back to 70 kts quite a lot and this worried the guy I was with who tapped the ASI and said not too slow... so more power in steep turns watch the speed???




On the other hand if I was in the Tommie at 45 deg and saw 70kts I would not be too concerned, but I would make sure it did not drop lower...


Fuel is another thing that sort of bothers me about the AA1C, I always fly on the numbers ... i.e. time, fuel gauges in GA as well all know b*ll*cks right. But I do like to dip the tanks to keep a check on fuel burn. Can't do that with the Lynx,... so I think keeping an accurate fuel log and recording the top up numbers when refuelling mid point is a must... I'd really rather dip the tanks.


My over all feeling is it handles like a Tommie, but you need to watch the speed/drag curve, weight and T/O run (at least the trim is better!!!!) sound about right PPRUNERS?


Thanks to those who replied, 800m grass strip sounds about right for this plane.


FK73

olympus
6th Mar 2017, 19:08
Quote:
(I will never spin this AC BTW)


Absolutely vital. Back in the 70s, the CFI of the company I rented from, insisted on demonstrating a spin to a newly-hired instructor, inspite of the prominent NO SPINNING placard. The spin went flat, the CFI was killed and the new instructor was crippled for life.

The instructor with whom I did most of my flying training back in the sixties was also killed in an AA-1 spinning accident. Sadly his student also died. New Year's Day 1971 - always remembered.

EddieHeli
6th Mar 2017, 20:14
I owned one for a while (AA1 B modified)
There are sight tubes in the wing roots so you can see exactly how much fuel you have, so no problem with not being able to dip the tanks. But they only have small tanks so limited in range/endurance.
They fly nicely, like a little fighter with those short wings, but I had a few bum clenching moments on takeoff with the long ground roll. Be careful on sideways sloping runways because the castoring nosewheel and small rudder means you have to drag the brakes on one side a bit until the speed builds up lengthening the takeoff roll even further. I had to break right on takeoff from Popham when taking off towards the trees once for this reason, raising the heart rate a bit.
I also had a few moments at Sywell where I was based when the fence at the end of the 750m grass runway was getting very close before liftoff on low wind days.
But great to fly once in the air.

flyingkiwi73
6th Mar 2017, 20:48
yep I'm never spinning one,... and I have myself mentally briefed for the INSTANT recovery if one occurs at altitude (through wing drop stall recovery practice etc..) ,... low down I'm gonna make sure it never happens.

India Four Two
6th Mar 2017, 21:56
My over all feeling is it handles like a Tommie, but you need to watch the speed/drag curve, weight and T/O run (at least the trim is better!!!!) sound about right PPRUNERS?

Sounds OK to me. Fly the aeroplane and pay attention. :)

BTW I'm not a Kiwi, but I've done enough flying there, mainly at NZTG, to have picked up the local lingo - "Stearman 03, lifthand downwind for the seal" and of course "Kia ora, I'll have sex iggs, please bro." ;)

flyingkiwi73
7th Mar 2017, 21:27
Thanks all.


@eddieheli Yeah I think I will not be taking the Lynx out of anything less than 700m with out some good headwind. luckily some of the smaller airfields have alternative vectors... i'll take the xwind if the wind is that light!


I've heard the sight tubes aren't to accurate??? mind you I normally fly on the stop watch anyway!


@India four Two, that is a nice approximation of the kiwi "ackSent" :-)


if you are around NZPP you'd probably hear "Pram truffic, Pyper tummahawk Tungo Dulta Lima is dunwind for runway three fur seal, foal stup"


then we'd get out and go for a cool glass of "Mulk" and "fush and chups" :ok:

India Four Two
8th Mar 2017, 04:22
Great "fush and chups" on the wharf at TG!

My Canadian son-in-law lived in Wellington for eight years. Consequently, he will answer to either Jeff or Jiff!